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how to extend support for EXT4 file system for microSD cards in stock or non lineage / CyanogenMod ROMS
As  I am aware after Android 4.4 or some sort your storage card is no longer eXposed directly and needs to be carefully interfaced through specific Mount points that need to be aware through vold  system

My question is given this situation and the fact that ext4 is very complicated in terms of of access and especially with now SeLinux sitting on top of it
it is somehow still possible to render ext4 support when it did not exist initialy as has been the case for lineage and previous similar OS's
that would be the case if the mount points  are created at boot time and then vold is made aware of them

what I did
since I am rooted ( magisk ) I use su mount master and mounted these manually but trying to then use vold failed because it was too late
I found some articles about how how this was achieved in earlier Android versions upto 5.
after 7.6 Android world has become even more paranoid on security and seLINUX couldn't have been more fussier
from 7.x onwards Android versions I would like to know if there is a definitive guide about how this can be done .I do not mind recompiling this feature in the kernel. this is a far more rewarding investment then trying to look for custom ROMs and moving away from stock just because you want EXT4support

so how do I I add
EXT4support on stock  and similar ROMs
for Android versions > 7.x and do this the right way where all apps can access my partitions. all my partitions are
EXT4 this is quite in contrast to the the second partition app2sd approach that is used to save space. of course I have that as well but I have two more partitions used for extSD ( main external data storage partition ) and one devoted to to another app. totally 3
EXT4 partitions . first one is the main data partition ,2nd is app2sd and third is a special partition devoted to one app.
if it matters I am rooted on a Samsung device running stock nougat 7.x.
another thing that I observed and I will update the question accordingly is all of a sudden out of nowhere  partitions mounted under /storage are now read only earlier they were not so. I can still read write to them through /mnt/media_rw I wonder what went wrong because lot of apps depend on accessing my partitions through /storage Mount point.
So just to summarise here  are the questions:

Mount multi ext4 partitioned external card at boot time, as against manual mounting which I can do.
Mount it the correct way with the right group ID, so that vold gets to know it has been mounted and all apps and process can freely access the partition.
All external partitions under /storage suddenly became read only (internal memory partition is of course read write always). tune2fs confirmed that all partitions are clean. Why does this happen and how can it be fixed?

thanks for response. I put this question that sounded like a narrative since I did not have screenshots or logs at hand if that is what you meant in your opening comment in answer. So here's what I am trying to achieve but run into all kinds of errors.
 1) Mount mmck1p2 to /data/sdext2 and I keep getting error failed to mount ...mmcblk1p2 on .....invalid argument  & another similar line  failed..... /dev/block/vold/public on .... invalid args. that is via app2sd and my magisk has global option turned on
the same partition is already  mounted  at boot under media_rw and storage

Bind mounting  camera DCIM and many other folders in internal storage  fails  when   target  is /storage/part# & it  earlier worked well. My partitions are clean as per tune2fs report . What happened ?
Thanks again. Answering  your Q's here :
1) What are currently mounted filesystems (output of mount)?

o/p is too big to fit in here. PFA
2) Output of /system/bin/id?
for  normal user
uid=10112(u0_a112) gid=10112(u0_a112) groups=10112(u0_a112),1015(sdcard_rw),1023(media_rw),1028(sdcard_r),3003(inet),9997(everybody),50112(all_a112) context=u:r:untrusted_app:s0:c512,c768

3) What command exactly did you use to mount mmck1p2 to /data/sdext2? 4) What command exactly did you use to bind mount DCIM folder?

1   mount -o,rw /dev/block/mmcblk1p1 /storage/extsd
2   lp=/sdcard/logger.txt
4   ls./mnt/media_rw
5   ls /mnt/media_rw
6   mkdir -p $_/extsd
7   mount --bind /storage/extsd  $_
8   ls $_

with above run from terminal I am able to see files from terminal only. if run from adb I get the same situation . Thought adb would be persistent but ain't the case.
after that I tried to invoke vold with the hope it would make my mount persistent and visible but no  luck there either
dreameltemtr:/ # /system/bin/vold
/system/bin/vold
Aborted
134|dreameltemtr:/ # /system/bin/vold --blkid_context=u:r:blkid:s0 --blkid_untrusted_context=u:r:blkid_untrusted:s0 --fsck_context=u:r:fsck:s0 --fsck_untrusted_context=u:
r:fsck_untrusted:s0
ntext=u:r:fsck:s0 --fsck_untrusted_context=u:r:fsck_untrusted:s0              <
SELinux selinux_android_compute_policy_index : Policy Index[2],  Con:u:r:magisk:s0 RAM:SEPF_SECMOBILE_7.1.1_0003, [-1 -1 -1 -1 0 1]

also to mount partition # 2 via app2sd  there is a mount script that  the app writes to /system/bin/etc or /data/app2sd dir's depending on the opts you choose. It uses the similar approach except that
-- I used its own binary for the bind mount functionality
-- I will do periodic tests to see if certain partitions get mounted
-- It will run these periodically ( kind of patched many scripts together  ) hoping that one will work
-- I attempts to mount via block device  ( /dev/block/mmcxxx) as well as vold ( /dev/block/vold/nnn)

Here is that script & you will see what I just said  . Again PFA since there is a ceiling to max chars on a post.
4) What are exact error messages? –
 exact messsages are 2 lines  from app2sd gui attention box
- Failed to mount /dev/block/ mmcblk1p2 to /data/sdext2 invalid argument

- Failed to mount /dev/block/vold/public/179:34 to /data/sdext2 invalid argument

On the last part where I cant write to external partitions mounted under /storage
That instance of ROM install was abortive . It caused repeated boot-loops after 10 mins so I just restored my Nandroid backup. So I cant dig out more details .

You can format external SD card as ext4 and mount it manually wherever you want. ext4 support is present on every ROM - stock or custom - since the first release of Android. What exactly your question is?

Thank you for responding Irfan I can found it manually as I have written so

Thank you for responding Irfan I can found it manually as I have written so . There are 3 questions sorry if it was not clear 1 ) it needs to mount at boot time and read write 2 ) the mounting information needs to be transferred so as to say to v o l d process so all other processes and apps can access that external data storage partition

3 ) another thing that I observed and I will update the question accordingly is all of a sudden out of nowhere  partitions mounted under /storage are now read only earlier they were not so. I can still read write to them through /mnt/media_rw I wonder what went wrong because lot of apps depend on accessing my partitions through /storage Mount point.

please clarify if you looking for non-rooted solution. i guess your problem isn't the file system it is more related to app permissions. have a look at https://android.stackexchange.com/search?q=WRITE_EXTERNAL_STORAGE

@user1874594 1) What are currently mounted filesystems (output of mount)? 2) Output of /system/bin/id? 3) What command exactly did you use to mount mmck1p2 to /data/sdext2? 4) What command exactly did you use to bind mount DCIM folder? 5) What are exact error messages?

THanks again Irfan Theres a mount script that I will put out in the question. and also o/p of mount

added more details you asked for Irfan- Thanks !

@ALex thank you again. This ROM is permissive right out of the box

thanks  folks for your help. I finally got the mounting  to happen using

thanks  folks for your help. I finally got the mounting  to happen using fbind magisk module but it would not happen straight away. had to open the the script which was full of functions and one of the functions looked for Mount media read write  as a mountaing pt In /proc /partitions.  & it never came out to be true with a time out of 1800 s.this function had to be to tweaked so that the result will be true when ,/mnt was mounted  and then the Mounting would happen.  hopefully the time I have invested in all this will pay off with this same module being used every time I  face this !

I don't think I understand your question fully. It's not clear what and how you have tried so far and faced what constraints or limitations in achieving what you want to. But precisely answering your questions:

Mount multi ext4 partitioned external card at boot time, as against manual mounting which I can do

Mounting external SD card is handled by vold. You can disable that in fstab and define an init service or put an init.d script to mount the partitions on boot the way you want.

Mount it the correct way with the right group ID, so that vold gets to know it has been mounted and all apps and process can freely access the partition

Since Android 6, in Portable Storage mode, vold mounts external SD card at /mnt/media_rw/[UUID] and then emulates that to /storage/[UUID]. Apps with WRITE_MEDIA_STORAGE permission (which is mapped to GID media_rw (1023)) have filesystem level write access to external SD card. But third party apps cannot write to SD card because the said permission has signature|privileged protection level. Emulation makes it possible for apps to read whole SD card but write only to their private directories. Also apps may use Android APIs (like SAF) to save files on SD card. See details in How to move files to external SD card?
This whole phenomenon is deeply integrated in Android framework - Java and native. So if you want to change this behavior, you need to modify Android source and rebuild ROM. Or don't rely on vold and mount partitions yourself with correct permissions as I mentioned earlier.

All external partitions under /storage suddenly became read only

There can be multiple possible reasons, you can check kernel log or Android log to see what exactly happens when you do mount -o rw,remount. Mounting read-only can be a sign of errors due to flash chip degradation. Or may be the partition(s) simply reached their maximum mount count, so you need to run fsck.

THanks for replying. I gave these details you asked for much as I could  dig em out.  What I want to get from all this is on a ROM  that does not support ext4  for  sdcard  like CM or Lineage , how can I have this functionality so that every time I dont have to flash a new Lineage ROM & then deal with its other short comings. Hope i am clear by now. Now for this instance I dont see /etc/init.d folder there is a init folder & even if I remount rw. Reboot will del scripts . i can put them in xbin but not sure if they will be executed.


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How to make a "system" screenshot with ButtonMapper
Since a recent update of ButtonMapper the functionality to make a "system screenshot" (if you have root) seemed to be replaced by a "app screenshot", which is limited in some apps as Instagram of Snapchat and also makes a very annoying clicker sound. I understand non rooted users prefer this over nothing. But I like to have my "system screenshot" back when I long press the Volume Down button.
I bought the Pro version of ButtonMapper and I have root access. Can someone please tell me how I can assign my "system screenshot" functionality back to long press Volume Down in Button Mapper? I miss it so hard.

the developer build this in but you have to know...
if you want a system screenshot instead of a limited app screenshot
do the following in ButtonMapper:

be sure to have root access
press the 3 dots
select "check for root"
now assign the screenshot functionality again to the desired button
ButtonMapper is making a "system screenshot" instead of an "app screenshot"!

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

sort: votes


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K9 not showing all mails in unified inbox
I noticed recently that K9 is showing emails in individual folders, but no longer in the Unified Inbox. That still exists but has had no new entry in the last few weeks.
I have changed nothing in configuration, although it is possible that I got a new version of K9 in a bulk update.
Any idea what I might be doing wrong, or how to get it working again?

Look at the icons at the bottom of the screen. The middle of the five looks like three bars of different lengths:
-------
------
----

that is the sort key and I must have accidentally "pocket dialed it".
Sorting by date made it clear to me that all emails are being shown in the unified inbox.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
Prevent automatic redirects in Mobile Firefox for Android
How can I turn disable redirects in Firefox for Android?
Here is a solution that works for desktop Firefox:
Prevent automatic redirects in Firefox
Unfortunately the accessibility.blockautorefresh option is not present in Firefox for Android.

As noted in this answer from the same question you linked, you can use network.http.redirection-limit to block redirects. Start by setting it to 0 (instead of 1 as in the linked answer). It will will have the effects of blocking all redirects and even accessing any site.
Then increasing with the value will allow depending on the site to allow redirects (or clicking "Try again" when the redict was blocked).

OP is asking for Android


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Restrict contacts from knowing I am on WhatsApp
Am I right in understanding that when one installs whatsapp everyone in the contacts on my phone knows I am on whatsapp (at least the ones who have whatsapp)
I do not want the above to happen. So if I put in another SIM card, then can I avoid the contacts on my primary SIM knowing I am on whatsapp and restrict to only the contacts on the new/secondary SIM. Or will WhatApp anyway broadcast to all contacts on all SIMs?
My basic aim is to expose the fact that I have whatsapp to a limited set of people - hence the second SIM.
Kindly let me know
Ananth

Hello. Follow this: https://android.stackexchange.com/q/201826/96277

@Firelord This is more from a standpoint of one SIM of contacts and WhatsApp with that number and to limit the contacts visible. I think DUAL SIM is equivalent to what you said if you set up the second SIM with only contacts you want on WhatsApp. So your primary SIM and all its contacts dont know you use WhatsApp - at least this is my understanding from the answer below from NatWeb Solutions

Simple answer to your question is - everyone who has your new number will see that you are on WhatsApp. WhatsApp is tied to mobile number only and it will not "broadcast to any other sim". If you don't give this number to another person then they will not be able to  see or contact you.
Also a hint. If you have dual SIM phone you can use normal WhatsApp and business WhatsApp (it's free) on the same phone simultaneously (using 2 different numbers).

Cool. So if I put in another new SIM and use its number while installing/verifying WhatsApp only those people who get this new SIM's number will be able to see me on WhatsApp. All contacts on my current SIM will remain unaware of my WhatsApp usage - is my understanding correct? If so that is exactly what I want. I dont want to use whatsapp at all but my small business if forcing me to do so, hence I want this demarcation. We already have another number which is WhatsApp business so I do not need that. Please confirm my understanding before I go ahead with the plan :) Thanks for the help !

@ananth yes that is correct:) you can use new number and only people who will have that number will see you have WhatsApp on it.

Thank you so much. Will get my second SIM and get that number set up as my WhatsApp number. Appreciate the help :)


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Android - is there any negative impact when you wipe out RAM and CACHE data for all Apps at once?
in Android phones, there are settings related to the phone's internal storage.
I am interested in two of those settings, "delete all RAM data for all Apps", & "delete all CACHED data for all Apps", because each is larger than 100MB already according to the displayed info.

I thought until now that "cache" is part of "RAM"? Or what is the difference? There are two different options available so there must be some kind of difference I guess.
I like to know if it is totally OK to delete those 2 things (ram+cache) from time to time (& for all apps)? I know that deleting cache has no negative effect, because I deleted cache of apps sometimes. But I never deleted RAM data. And the thing is also, the setting says "...for ALL apps". So there are apps like "contacts" "calendar" or other system relevant apps included. I am not sure if you can wipe RAM/cache of those kind of apps, too?

Thank you for help

Cache is on persistent storage, which the OS itself clears as the storage runs short. You can also clear that manually for individual or all apps. RAM is volatile memory which the kernel allocates as the processes are created, executed, exited and killed. So clearing RAM doesn't make sense to me.

Is it safe to manually “clear cache” of apps on Android?

I thought until now that "cache" is part of "RAM"? Or what is the difference? There are two different options available so there must be some kind of difference I guess.

RAM is the space in main memory used by running processes. Similar to the RAM used in desktops and laptops.
Cached data includes the files, images, scripts and other media files stored on your device by an website or app. Data is stored on your devices in a reserved space, so the next time when you are visiting the app or website, information is already available.

I like to know if it is totally OK to delete those 2 things (ram+cache) from time to time (& for all apps)? I know that deleting cache has no negative effect, because I deleted cache of apps sometimes. But I never deleted RAM data. And the thing is also, the setting says "...for ALL apps". So there are apps like "contacts" "calendar" or other system relevant apps included. I am not sure if you can wipe RAM/cache of those kind of apps, too?

There is no problem if you clear cache and RAM. In fact, you should do that regularly to keep your phone efficient. Even after you clear RAM, some processes would restart; so ignore them. Otherwise it would stop all processes that are not being utilised at the moment.

thx. Cache is all right. but why do you think RAM is ok to clean regularly?  The apps will either way -restart automatically again and the RAM will increase again.  Or do you assume there could be Apps running, which after clearing RAM, would NOT restart again?

It is absolutely okay to clear RAM. If you are working on some app, then don't clear the RAM, because you would have to open the app once again. For eg, if you are downloading something on chrome, clearing RAM will stop the download as chrome will close, and you have to manually start it again. But if your device is idle, there will be NO problem if you clear the RAM. Processes like that of social media apps will restart themselves when required. In other words, there would be no app that would not be able to restart itself if it requires to do so.

But remember clearing RAM will free up space to make your phone fast, it will not give you space where you can save your photos and media, unlike cache. Read this: https://www.androidpit.com/ram-management-on-android


text:
Clock app freezes
The app that is responsible for clocks keeps freezing. The lock screen widget, the normal widget, the status bar clock and the clock inside the app itself all occasionally show incorrect time (usualy between 10 minutes and couple hours before current time; not even always the same). Alarms won't work when this happens and lately it has been happening multiple times a day. When the clock gets "unstuck" it just jumps right to the correct time and sometimes freezes again. The internal phone clock probably work fine based on what the other apps show. It started about 3 months ago as once-in-a-week thing and has been happening daily for a month now (so I obviously restarted it many times during that time).
The device is Hammer MyPhone Energy with Android 7.0. and it is not even a full year old.

The variety of durations where this is noticed is symptomatic of Performance Enhancement apps closing other apps when in the background. Check your system for 'Performance' or 'Battery Saver' to designate your clock app as exempt from closure. Sorry, I don't read Polish, so I can't lead you to the right place in its user manual found here.

Thanks, I found user manual here, the english starts on 15th page, but I didn't manage to find any relevant info in there.

Check whether the automatic time and timezone synchronization are set on the Settings, then try turning off and see if the issue still persists. Also, does the clock freeze until the "seconds" part? The date-time is actually persisted in the system, and all clock-related apps/widgets only retrieve the value from there.  The strange things are the status bar and alarms since they are also usually managed by system, not app. This might indicate there's something wrong at the system level.


text:
How to extract/backup your phone contact list and browser bookmarks (stock browser, not chrome)
Android - how to extract/backup your phone contact list and browser favorites (stock browser, not chrome) - a modern Samsung smartphone.
Hi, I am grateful for any replies (pls note that we always talk about a non-rooted device, and I have no desire to root it, & I have no desire to use the inherent google-backup methods):
1)   How can I extract my entire contacts list in a way to be able to import it again to another similar Samsung phone? Any way to do it without using an App for it as workaround? If there is no way around an app, which app(s) would you suggest are considered to be very "safe" and 100% non-malicious?
2)   The same question - this time for calendar items extraction?
3)   Finallly the same question for my Android Stock Browser bookmarks (not chrome)? Both, the bookmarks which are available in the "Normal" browser mode, and the bookmarks which are separately stored in the "private" browser mode.
If you know also of a way to doing one of those 3 things but without the ability to import again to another phone, this is also very helpful. My prime interest is in backing up, and if I can import again to another Phone, even better.
Thanks for any technical explanations!

Depending on your intended recipient the Samsung SmartSwitch application can do everything you want.
It can back up contacts, calendars, applications and almost all other data.
It's primary use is in transferring files to a new phone, but it also has a mode to transfer data to a backup held on your MicroSD card.
In order to simply backup data in the current version you will see an icon representing a microSD card in the top right corner of the application when you launch it, next to the three dot "menu" icon.
On the next page you will see either a list of backups or "no backup" if this is your first. Tap the "Back up" button at the bottom of the page.
Tapping that will bring you to a screen that allows you to select contacts, applications and images (and so on) to back up.
Your Calendar and bookmarks are stored under those applications. If you connect to Google calendar and don't use the on-device calendars then you will have a warning telling you as much when you tap on the ">" icon next to "Applications".
You can then transfer the backup to a new phone and use Smart Switch to restore it, or you can simply keep the history.
It also has a Windows version, presumably primarily intended as a backup tool.

The apps i'm going to propose are available through F-Droid. The name F-Droid refers to both A.) a repository for open source android apps and to B.) an android app used to browse, download, install an manage those apps on your android device.
You might want to check out this tutorial for information on how to install F-Droid or apk-files downloaded from F-Droid.
If you don't want to use F-Droid or sideload apps on your device, maybe you can find some of these apps in the Play Store as well.
1)
The Contacts app in android normally has a feature to import or export the contacts to a text file (.vcf). If it doesn't you can install this open source contacts app that can definitely do it:
https://f-droid.org/app/com.simplemobiletools.contacts.pro
2)
This depends on how you store your calendar events. In Android, it is common to store the events in a certain calendar, usually tied to an E-Mail account, this can also be your google account. In these cases, the calendar events are stored online with your E-Mail provider and should be accesible from any device with that Mail account properly set up for calendar syncing. If there is a website where you can log in and check your mail, chances are there is a calendar function on that site as well. If you can log into your Mail account using a normal browser and find your calendar events there, they are already backed up to the server of your Mail Provider.
If you want a local backup of these Events or keep them stored in a local calendar on your device, https://f-droid.org/app/org.sufficientlysecure.ical can export and import your calendar events to and from .ics files.
Note that the Android Calendar backend might discard passed events, in which case they cannot be exported using this method.
If your events are stored in your E-Mail account, chances are that these passed events that are no longer displayed/exportable on your Android device are still available online and stay stored on the server of your E-Mail provider - Android usually just stops syncing these events and removes them from your calendar view.
3)
For the default preinstalled browser in android it is also possible to back up and restore bookmarks. From F-Droid https://f-droid.org/app/de.shandschuh.slightbackup can do it.
Though, it should be mentioned that this app hasn't been updated a long time and might thus not work too well with modern versions of android. Since i don't use the bookmark feature i can't attest how good it works but giving it a try shouldn't hurt either - as long as you don't try to restore data before testing that nothing gets deleted or overwritten on the device where you want to restore you shouldn't lose any data by trying.
As you stated that you are using a samsung phone the browser will likely be custom made by samsung, so your best bet would probably be finding an export function built into the browser.
If the same circumstances described here apply to your browser app, your chances don't look very good.


text:
A/B partitioning - which slot is really flashed?
I have a Moto Z3 Play with stock ROM and rooted it by Magisk. Phone is seamless updates and treble ready. Everything works fine. Yesterday system updater was trying to update to the newest version but it fails. I know, I changed boot partition so it can fail. I downloaded a full ROM zip file from Lenovo servers (PPWS29.131-27-1-15), unpack it and trying to flash the newest version by myself using fastboot.
The current slot was B, it contained PPWS29.131-27-1-11 version. So I changed to A and flashed all partitions from PPWS29.131-27-1-15 ZIP file on slot A.
Commands that I used to flash PPWS29.131-27-1-15:
fastboot getvar max-sparse-size
fastboot oem fb_mode_set
fastboot set_active a
fastboot flash partition gpt.bin
fastboot flash bootloader bootloader.img
fastboot flash modem NON-HLOS.bin
fastboot flash fsg fsg.mbn
fastboot erase modemst1
fastboot erase modemst2
fastboot flash bluetooth BTFM.bin
fastboot flash dsp dspso.bin
fastboot flash logo logo.bin
fastboot flash boot boot.img
fastboot flash system system.img_sparsechunk.0
fastboot flash system system.img_sparsechunk.1
fastboot flash system system.img_sparsechunk.2
fastboot flash system system.img_sparsechunk.3
fastboot flash system system.img_sparsechunk.4
fastboot flash system system.img_sparsechunk.5
fastboot flash vendor vendor.img_sparsechunk.0
fastboot flash vendor vendor.img_sparsechunk.1
fastboot flash oem oem.img
fastboot erase carrier
fastboot erase ddr
fastboot oem fb_mode_clear

Then I tried to boot from A slot but it fails. The phone got bootloop and lands in stock recovery. I assumed that something goes wrong so I rebooted to bootloader and changed slot to B to boot PPWS29.131-27-1-11 version which was working fine. And then comes mindf*ck - after system start from slot B, I noticed that system version is now PPWS29.131-27-1-15. But how? I flashed partitions on A slot, not B. Even fastboot logs showed that I was flashing A slot.
When I changed slot to A with fastboot command is it really flash A partitions? Or just change which partition should boot in the next reboot?

question updated

This seems kinda weird to me. The fastboot images for the A/B devices I've seen so far explicitly flashes system_a and/or system_b, not just system. Your behaviour is more akin to flashing zip-formatted ROMs from recovery, where the recovery will flash it to the inactive slot and activate it afterwards, so that A/B take turns on each flash and you always have a fallback. Perhaps you used the wrong commands (for older devices?), because I searched and found references on XDA where Z3 Play is shown to also use _a/_b.

If you do not specify _a or _b suffix fastboot will flash on the active slot. You can check which slot is active by fastboot getvar all command. Changing active slot: fastboot set_active a. https://source.android.com/devices/tech/ota/ab/ab_implement. I'm starting suspect that in fastboot it can work like in TWRP, like you said. Active is B. I changed to A so fastboot start flashing on B, the other slot.


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I was checking my log of netguard ... and then I saw this ... is normal?
I was checking my log of netguard ... and then I saw this ... now im freaked

ampproject.org is the website for the Amp project developed by Google and it is normal.
“Amp is a web component framework and a website publishing technology developed by Google which has the mission to provide a user-first format for web content"

+1 it would be even better if you post the source link.


text:
Disabling "Ok Google" detection on Google Pixel 3a
I wanted to start using Pixel 3a (my old Nexus 5X is outdated) but I wasn't able to disable "Ok Google". I disabled all that was possible and recommended by a few how-tos but not successful.
Did I miss something when I bought this new phone? Where can I disable this?
This question is possibly strictly connected to googles pixel 3(a)
(dont remove that from the question)

Disabled and yet, phone is allways listening and after saying "ok google" it opens a dialog.

Your Google Assistant may allow you to designate the language. Try a really obscure language, if you don't find means to disable it completely.


text:
TWRP: Could not mount /data (even after format data / change file system)
I'm trying to root a Vernee M5. I installed TWRP - which worked - and tried to use it to install Magisk - which didn't work (my guess is because of encryption?).
Now the phone always boots into recovery/TWRP and I want to install the factory ROM so I can try rooting it again.
However, using TWRP to install the ROM fails with the error:
[...]
Updating partition details...
Failed to mount '/data' (Invalid argument)
...done

Rebooting the device opens TWRP again.
I tried Wipe -> Format Data -> yes, which also fails:
[...]
Updating partition details...
Failed to mount '/data' (Invalid argument)
...done
Unable to mount storage

I also tried Wipe -> Advanced Wipe -> Data -> Repair or Change File System. Changing the file system fails with the above error message. Repair also results in an error:
/sbin/e2fsck -fp /dev/block/mmcblk0p48 process ended with ERROR: 8

Some additional info: TWRP is not asking for a password anymore when booting. Internal Storage is shown as 0mb on "install", but it does still contain a folder structure. The console also shows that full SELinux support is present & MTP is enabled.
How can I fix these errors and install the factory ROM?

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While formatting with twrp results in an error, formatting with fastboot worked for me:

start phone, which will boot into twrp
reboot -> bootloader
fastboot format:ext4 userdata. This will of course delete all data from the phone.


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How can I copy the email address of the recipient when I compose a new email in Microsoft Outlook for Android?
I am composing a new email in Microsoft Outlook for Android and would like to copy the email address of the recipient;

How can I copy the email address of the recipient when I compose a new email in Microsoft Outlook for Android?

You can't copy email addresses that are already "formatted" as in your image when using Outlook for Android. While other email apps offer this basic feature, Microsoft simply does not implement it.
You must either enter the full email manually then copy it. Or search for the email (using the search tool), when found, click on the email address next to the envelope. A window will appear with "Copy" as an option.


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stop google maps from spinning the map
I used to be able to keep north up. Now not only does north move, sometimes the map will spin. Usually when I try to zoom (at least this is when I notice it). Even when it does not spin, the map rotates to put direction of travel up. This is confusing: I feel that I never know where I am.
Is there a way to force north to stay up? How do I activate it?
This is important to me, because last night I had to stop for 5 minutes, to figure out where I was, and which way to go next. (the spinning made me lost)

In Google Maps (Android version 10.49.2, also tested on 8.1.0). Enter maps' and access the Settings menu by pressing the profile icon at the top-right corner. Scroll down and press the Navigation settings, then scroll down to Map display section, and switch on Keep map north up.

Confirmed to work on android 8.1


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Can I save system app data from being erased?
I have app that is installed in the system , my question if there is a way to prevent factory reset from erasing app data , no need to change the settings again ,without using backup app , atomic process after the phone has started working after factory reset

App data is saved on /data partition which is completely erased with factory reset. So there is no way to retain data except backup/restore (backup app isn't necessarily required) or devise some way to make data available on boot from some other source which is not erased with factory reset e.g. external SD card or some partition on internal storage.

Can you explain more? if there is a specific way that i can restore data without using backup app it would be so helpful

Use adb backup, create tar file from commandline, manually copy paste data directory of the app from custom recovery, create a flashable zip to backup/restore data easily etc. Possibly other approaches too.


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Where is the baseband firmware stored and how does Android interact with it?
My searches on the web didn't provide suitable answers to these questions:
1) Where is the baseband firmware stored?
My understanding is that this particular firmware is a RTOS built for the Baseband Processor (BP/CP). BP is part of a SoC, so it uses its own RAM and its own storage for the firmware.
Is the firmware really stored in another eMMC than the Android firmware ?
2) How does Android interact with the baseband firmware?
Again, my understanding (which may be incorrect) is that the BP communicates directly with the AP via a serial connection UART trough Radio Interface Layer (RIL). This RIL interact with Android telephony services.
When does the baseband firmware take action ?
3) When the modem/baseband/radio partition is used  ?
It seems to me that it only contains the firmware.
One thing I've found is that this partition isn't mounted during Android runtime. Is it only mounted for modem firmware update ?

rmt_storage also provides BP access to IMEI which is stored on signed partitions like EFS, MODEMST1, MODEMST2, FSG, FSC along with modem firmware files. MODEM is usually first partition with FAT filesystem. All or some of these partitions may get firmware updates from OEM/SoC vendor. Like rmt_storage, rild is a closed source binary from vendor which facilitates communication between Android (telephony stack) and BP through kernel. Fingerprint, rmnet LTE/3G interface, RPM, TEE, GPS, Modem Diagnostic Mode etc. also communicate with AP using SMD or possibly UART, and their userspace blobs

Is the firmware really stored in another eMMC than the Android firmware?

No. Baseband firmware, kernel and userspace Android are all stored on the same eMMC (there might be some exception but I don't know of). Some SoCs have boot area partitions which are somewhat isolated at hardware level (usually used for bootloaders) but technically those are also on the same eMMC. So are Replay Protected Memory Block (RPMB) partitions.

How does Android interact with the baseband firmware?

Your understanding is correct that Communication / Baseband Processors (CP/BP or modem) are completely isolated from Application Processor (AP, which runs Android OS) and they run their own RTOS. Communication between AP and BP can be through multiple possible channels but mostly those are proprietary just like BPs themselves (not sure why: if giants like Qualcomm are keeping backdoors, or hiding their security vulnerabilities, or don't want to put users' privacy at stake). On Qualcomm devices, for instance, its in-kernel implementation is called Shared Memory Device/Driver (SMD).
BP also includes a Digital Signal Processor (DSP) which is used for multimedia processing. Both Modem and DSP have their mountable partitions on eMMC (at least on Qualcomm devices) which they access through kernel using RPC mechanism. This old document states:

"No new hardware is required. An eMMC card will have 2 partitions reserved for modem storage.
  ...
  All the modem requests will be handled by a user space program and the remote storage RPC client will provide an interface to the user application to receive the requests from modem and also to send the status of requests to modem."

In-kernel implementation includes just an RPC client, while a closed source userspace daemon (Remote Storage) handles the actual communication with the modem. Though privacy advocates have issues with this approach. Since the kernel interfaces of SMD or other communication drivers are not documented, only the closed source binary blobs (HALs, provided by SoC vendors) in userspace can communicate with them (e.g. rmt_storage uses Userspace I/O API), while Android framework communicates with the HALs. Reference implementations of HALs are part of AOSP.

Is it only mounted for modem firmware update?

No. MODEM is usually first partition on eMMC with FAT filesystem, while DSP has EXT4. Both have entries in fstab and are mounted on every boot. rmt_storage also provides BP access to IMEI which is stored on signed partitions like EFS, MODEMST1, MODEMST2, FSG, FSC along with modem firmware files. All of these partitions have no filesystems but are binary blobs written to raw partitions. So they aren't mounted. All or some of these partitions may get OTA firmware updates from OEM/SoC vendors.
Like rmt_storage, Radio Interface Layer Daemon (rild) is another HAL from vendor which facilitates communication between Android's telephony stack and modem's LTE/3G/2G interface through kernel using control and data transfer protocols like RMNET, QMI etc. Other isolated components including RPM, GPS, Modem Diagnostic Mode and TEE (not sure about SE) also communicate with AP using similar communication channels in kernel (which also include UART) and their respective HALs in userspace. RPM (Resource and Power Management) and TEE (Qualcomm's TtustZone) have also their partitions on eMMC, both contain ELF executable binaries.

RESOURCES:

Android Device Partitions and Filesystems
A Journey into Hexagon: Dissecting Qualcomm Basebands


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Stuck on "Bootloader is unlocked" screen, can't boot into recovery
So I wanted to root my OnePlus 6 after updating to android 10
(OnePlus6Oxygen_22_OTA_041_all_1911142043_dde113e5 3cd0f9.zip)
I tried booting into twrp via fastboot using fastboot flash boot twrp.img
(twrp-3.3.1-x_blu_spark_v9.101_op6.img, my bootloader is unlocked).
I then tried rebooting directly into twrp, but now it's just stuck on the "Bootloader is unlocked" screen.
I can still boot into fastboot, but I can't boot into recovery or reboot normally since it just gets stuck on the bootloader unlocked screen.
Please Help!
Edit1: Changing my boot slot from b to a gives me access to the stock recovery. not sure where to go from here though.
Edit2: Fortunately, ManikandanGuru over at xda had uploaded the stock boot.img, which works perfectly.

the above fastboot command does flash twrp recovery permanently into boot partition, you can't reboot normally because boot.img is gone


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How to put Google Store on Chinese Samsung Note10+
I'm currently living in China and decided to buy the Samsung Note10+ (has Android 9 installed) (had an iPhone from America beforehand), I did not know the headache that awaited me. I know no Chinese (Mandarin) and I can't keep asking my Chinese relatives for translations on my phone, so while I set the phone's system language to English, I still have no access to Google services at all.
I had tried installing Google Play store (ver. 17.5.16), Google Play Services (ver. 19.8.29), and Google Account Manager (ver. 6.0.1) from the AndroidAPKsBox site (used this site since apkmirror and other apk sites are blocked), all apks installed EXCEPT for Google Play Services which says the app did not install but with no error code. Is this the incorrect Services apk that I need?
Right now, VPNs are being blocked, even ExpressVPN so I'm not able to visit a lot of other helpful sites except this one. I know Google Play can't be fully utilized until the VPN starts working but I wanted to at least have all that I need on my phone so I can start using Google Play right away when available.
Edit: I just realized that there are a lot of differnt variants of Services that have different architecture and screen DPI. My Note has a Qualcomm so I assume I should choose the download that's made for ARMx64 chips with nodpi, correct?

I found a Google Play Services for Arm64 nodpi download here, I installed it along with my current Google Play store and Google profile manager and now I'm able to download Google Play store apps without issue. The biggest obstacle was getting the right Google Play Services download.
For anyone else in the same position, APK Mirror is a Godsend as long as you know which version you need (this article helped greatly) and make sure you download the compatible gapps.


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Location Tracking as Evidence
With location tracking enabled in Android, I see entries in "Your Timeline" in Google Maps. I know it's possible to add/remove/edit entries in this timeline, but is there are a way to get a reliable, unmodified export of what has been tracked that could be used as evidence? I understand that tracking and times might not be 100% but I essentially want to see if there's a way to get a version similar to the KML export that hasn't been edited that I could say "this export can't be edited".
I've been told the red dots that appear on the map can't be edited and can be relied on but I'm not so sure if there's any non-editable version of Android's tracking history?

All personal data in your Google account, including timeline data, can be exported. here's an article showing how to do it.
https://helpdeskgeek.com/how-to/how-to-download-your-personal-data-from-google/

Thanks, but I didn't ask how to do it (I showed how I could do it in my question), but I want to know if there's a way to download said data without it being modified by any changes made via the gui.

Sorry, yes, misunderstood. I don't know but I think it's unlikely. If I deliberately removed removed an item from my timeline and somehow Google still retained it (in history or wherever) it would make a nonsense of being able to download everything Google holds on you. In my jurisdiction at least that would not satisfy  Google's legal responsibility.


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How do I NOT install the apps that Google Play Store offers for review?
I have a new Nokia 3.1. It immediately wanted to download updates, which it did successfully. Now I have a notification that I can't get rid of to "Complete setup by installing apps". When I touch it, I get this:

I can't seem to deselect these. How do I NOT download them, and not be bothered by the offer any more?

Solution found.
Hold on the notification and turn off notifications from play store.

You can make that annoying notification go away by disabling the Android Setup app

Got to Settings/Apps and notifications
Tap "All apps"
tap ... in the top right corner and select "Show system"
Search "Android setup" and disable the app, the notification disappears right away, including the one in the settings menu.

It happened in my Samsung A30s - Android 9.0.
I installed the recommended apps, the notification of Complete setup by installing apps gone, and I uninstalled them again.
I seems there is no easy way to get rid of that notification.

Try to switch over to mobile data and reboot your phone. Maybe this will hold off the auto-download from wifi.
You can also stop your updates by disabling auto-update in "Updates" section of "My apps and games".


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Why does MY WhatsApp web take so long to load?
If this question does not belong in Android please be kind enough to tell me where it does belong since I did find a whatsapp-messenger tag here and I thought this fits in Android Enthusiasts.
I do not understand why when I open web.whatsapp.com in a browser it takes so long to load and even reload!. I have not seen this problem with any of my friends and I tried myself with a different account it does not take that long.
Here is a video that shows it takes a short time with one account and here is a video that takes a long time with my main account. It takes 15 seconds longer at least!
I thought it might be because my WhatsApp backup files are very big, but I believe many people should then have the same problem. I also tried on many different browsers, deleted my backups and reset them and even reinstalled the app.
I attached a picture of the WhatsApp files on my phone maybe that helps, I use google drive backup on both accounts.

I know, right? The issue of it loading normally and fast and then all of a sudden it takes 15 seconds for all the imagery etc. to load in Whats app Web. The problem most likely is your browser; I test Chrome, Brave & Firefox (I use the last one by default) and turns out that Chrome loads nearly immediate, whereas Firefox loads the longest. Annoying, but nothing can be done as far as I know at the moment.
See link for more information.
https://menafn.com/1098516091/TechBytes-Handy-tips-to-avoid-WhatsApp-Web-loading-issues

First of all thanks for answering! I already tried different browsers and it still loads slow - I wrote this in the question but I'll add a video which does this. Could you add a video which shows that Chrome is fast and Firefox slow?

Also regarding the article - I did everything written in the article and I it's still loading slowly, as I explained in my question the problem is with my specific account since it does work faster with another account.


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Galaxy S6 edge sms not working
My Samsung  Galaxy S6 Edge (7.0 Nougat), cannot send basic sms messages, I have to add a Subject to every text. this makes having a conversation with anyone impossible. How can I restore this messaging app. This may have began with the last update to (7.0 Nougat), it was sudden. Samsung has been no help and I cannot afford a new phone. Any help would be appreciated.
Thanks, Rick.


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How can I make sure Google's "Find My Phone" works when my phone is in power saving mode?
I recently couldn't find my phone, so I used Google's Find My Phone web app to try to locate it. The service couldn't locate my phone, and though I'm not quite sure why (there are a sea of settings), my guess is because it was in low power mode (and not connected to WiFi).
My phone is a Galaxy S10e. What settings should I use to make sure Google Find My Phone can find my phone even in "low power mode"?
I know how to set special app permissions and give them usage of background data even in low power and/or mobile data mode. I'm just not sure which app to give the permission too.


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Media volume is changed when on a phone call
I'm using Android Pie on a Samsung Galaxy S9 phone.
I noticed if I set the media volume down all the way to mute it that the volume is turned up a bit only while on a call.
If anyone is experiencing this issue, it would be appreciated if you can tell me if there are any settings I can access to stop Android from adjusting the media volume while on a call taking it out of mute mode.

There is indeed a different volume bar for when you are on a call. I think the easiest way to set this is to change the volume whilst on a call, this will save the settings for the next time you're on a call. If you want to change the settings before you go on a call just phone someone yourself and change the settings, they don't even have to pick up for you to do so.
This is of course not ideal and I'll change the answer if I find a app or so that can do this.
You can not however mute the sound from a phone call.


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YouTube video in fullscreen mode being cropped
I have a phone Xiaomi Mi 9T with Android 9 and I have MIUI installed on it. My problem is that when watching videos on the mobile version of YouTube in fullscreen mode, videos are being cropped. Here is an example: YouTube video on my phone and PC.
On PC

On the phone in mobile version, you can see that the bottom part has been cropped.

I tried on Firefox and Chrome, it seems that every browser on my phone uses the same player, so videos are being cropped everywhere.
Also, if I use the desktop version of YouTube and open videos in fullscreen, then the player is cropped at the bottom.
On phone in fullscreen

Do you know how I can fix these?

Does this happen in the YouTube app as well? Did you try turning desktop mode on in Chrome for example?

@ChagaiFriedlander It doesn't happen in Youtube app, but I don't like to use it for other reasons, I would like to browse youtube in Chrome. I did attach an image with desktop mode in Chrome (the third image): you can see that the video is not being cropped but the player is.

Did you try zooming in AND out? Could you share the URL with us? Sometimes you can change the URL to make the website think it's running from a computer.

Have you heard of OG YouTube maybe that'll work for you.

@ChagaiFriedlander How do I zoom? I tried stretching with two fingers like an image, but it didn't zoom. Here is the link https://m.youtube.com/watch?v=xebewT6lh2k&t=2s. This is the mobile version. It would be nice if there is a way to fix this on mobile version.

Settings -> accessability -> enable force zoom. youtube.com/watch?v=xebewT6lh2k&t=2s try this link, without the m. At the beginning.

Did it work? Or do you still need help?

@ChagaiFriedlander I don't have enable force zoom. All my browsers use the same player when playing videos on youtube, I think I need to change the player. Is there a way?

Try adding this extension to Firefox. https://addons.mozilla.org/en-US/android/addon/external-video-player/

I had the same issue as you. Try using the Firefox browser, it worked for me.


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Zombie process using termux
I am testing one of my application on android's (Android version 7.0) termux terminal emulator.
I want to spawn some zombie processes.
On GNU/Linux, if I open a terminal emulator and write:
ruby -e '10.times { fork { exit! } } && sleep '

This will create 10 zombie processes. To check about zombie processes, I write:
ruby -e "puts Dir['/proc/**'].select { |x| File.split(x)[1].then { |y| y.to_i.to_s == y } }.then { |a| %<Active Processes: #{a.size} (#{a.count { |x| IO.readlines(%<#{x}/status>)[1].split[1] == ?Z.freeze} } Zombies)> }"

Which outputs in the format:
Active Processes: 189 (10 Zombies)

But on Termux, I can't create zombie processes. When I am forking a process, the process count doesn't increase (as reported by htop and the ruby program). Even if I try to spawn processes, it won't spawn any. I have total 11 processes showing on Termux!
What's so different about android? Is there any way to test my application using termux? Or are there any other applications that will allow me to do such stuff?

I just created 100 zombie processes on Termux using for n in {1..100}; do (sleep 1 & exec /bin/sleep 10) & done and they do exist for 10 seconds as expected, then reaped by init. To see zombie processes: ps axo stat,ppid,pid,cmd | grep ^Z. Or just to take count use grep -c ^Z.

I just created 100 zombie processes on Termux using:
for n in {1..100}; do (sleep 1 & exec sleep 10) & done

and they do exist for 10 seconds as expected, then reaped by init. To see zombie processes:
~$ ps axo stat,ppid,pid,cmd | grep ^Z

Or just to take count use grep -c ^Z.


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Huawei's Safe not found, how to recover the files?
I have Huawei Y5 (2019) running on Android 9 Pie, and I'm using its built-in Safe to secure my photos.

I made a Safe, put some photos in it, and made a password and it was working good.
Now, when I try to open it, I get this message and I can't find my photos.

Note
AMN-LX9 not found. Choose another Safe?

How to recover the photos?


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How do I know if an app on my phone makes use of App Bundles?
App bundles (or I believe it is because of them) are screwing me over with regards to Titanium backup since restore simply does not work with those - they are stuck on "restoring". Currently, I only have TiBu on old hardware where it takes very long to do stuff, and if it just says "restoring" I've no idea if it's actually doing anything. More apps will soon adopt this new feature and I want to be able to filter them out easily without wasting too much time.
Is there an ADB command maybe that can tell, or some other way with root?

I found an app called Split APKs Installer to help.
Google Play: https://play.google.com/store/apps/details?id=com.aefyr.sai

Why the downvote lol

Hi, I'm not the downvoter, but when suggesting an app, ideally its description and usage is also mentioned on the answer to also help future readers.

Honestly I'm not sure what's the exact use case for it. But it helped me solve my problem of knowing which apps on my device are split APKs, so ¯\(ツ)/¯


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Please help with Stock/Custom Rom for Bluboo s8a
I was trying to root bluboo s8a with TWRP following this tutorial
When I reached step 2 of installing the ROM with sp flash tools, the ROM installed up to the end but the phone stopped powering (doesn't show anything). I tried downloading other customs ROMs for bluboo s8 but they were customized to be flashed with TWRP because they had no scatter files.
I landed on one custom ROM which I flashed into the phone with sp flash tools and the phone powered on and I could hear the sound when I press the buttons and when the phone is powering on but the screen shows a dark screen.
I would like to go back to the stock ROM or a working custom ROM. I took some screenshots of the settings of the About Phone before trying the rooting process.

About Phone (click images for larger variants)
Update: Now I have gotten some ROM from the seller's website. It's in a zip file with one .cpb file and a folder named dbs. The folder has two files. When I try flashing the .cpb file with QGDP, I get an error of CPB Package is not complete. How can I overcome this please?

I finally got another ROM version which was extracted into .img files to use sp flash tools. I flashed the ROM with sp flash tools and the phone worked again.
Tools needed:

Sp flash Tool
Firmware

The link to the stock firmware/ stock ROM file for BLUBOO S8a _V27.20180314 is here
ps: credit goes to Rusya77@ Ruslan N and Samin Sikong


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can copy file from one folder but not another
I am trying to get an apk from the aurora directory on the device onto a linux pc. There is not an issue copying in and out of the Download directory. If I connect the device with a cable and right click on the folder and list its contents in the terminal, it looks like this:
cardamom@northsea:/run/user/1000/gvfs/mtp:host=%5Busb%7A019%2C004%7F/Interner Speicher $ ls -la
total 0
drwx------ 1 cardamom cardamom 0 Jan  1  1970 .
dr-x------ 1 cardamom cardamom 0 Jan  1  1970 ..
drwx------ 1 cardamom cardamom 0 Jan  5  2019 Alarms
drwx------ 1 cardamom cardamom 0 Jan  5  2019 Android
drwx------ 1 cardamom cardamom 0 Aug 11 18:53 Aurora
drwx------ 1 cardamom cardamom 0 Aug 26 08:35 DCIM
drwx------ 1 cardamom cardamom 0 Dec  8 10:41 Download
drwx------ 1 cardamom cardamom 0 Jan  5  2019 Movies
drwx------ 1 cardamom cardamom 0 Jan  5  2019 Music
drwx------ 1 cardamom cardamom 0 Jan  5  2019 Notifications
drwx------ 1 cardamom cardamom 0 Jan  5  2019 Pictures
drwx------ 1 cardamom cardamom 0 Jan  5  2019 Podcasts
drwx------ 1 cardamom cardamom 0 Jan  5  2019 Ringtones
drwx------ 1 cardamom cardamom 0 Jan  5  2019 storage

Now files from the Download folder can be copied to the PC without a problem but if I try it from Aurora, this happens:
cp: error reading 'app.some.app.330.apk': Input/output error

If I list the Download or the Aurora folder with ls -la, all files have the same permissions.
I tried the suggestions here but it did not really help.
Then I went into a file manager on the device - one called 'open manager' which I installed from FDroid and copied the file I wanted from Aurora to Downloads. Now it gets strange - the file is visible in Downloads in the file manager on the device, but nowhere to be seen in Download when looking over usb!
Any ideas what is happening, how to remedy it?

your question is about mtp, but have you tried adb it is a simple command line alternative. you need android-tools-adb (android-tools-fastboot is not required but recommended to install too) and you must enable usb-debugging in developer options. regarding "not visible" reconnect mtp each time something has changed. Input/output error sounds like dirty file system

Ok thanks, that worked, but it took me a long time to work out how to get to the sdcard through adb shell, give adb shell root access then do a pull command. Also ran remount. Last command to do it was adb pull /mnt/sdcard/Aurora/app.some.app.330.apk Following links are useful 1, 2

mtp itself is just a file transfer protocol based on client-server request/response model. GVfs is a virtual filesystem which uses mtp as a back-end to let programs like Nautilus and Thunar (which use GIO library) to explore files remotely. However it's not meant to be used on CLI. You may use FUSE-based mtpfs or adbfs to mount phone storage as a filesystem. // Invisible file is due to buggy MTP implementation, see answer here: https://android.stackexchange.com/a/209119/218526


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How to limit the 'User Data' size of Firefox Android?
The User Data of Firefox Android goes on increasing every day..
To reduce it, I have to clear storage data and personalize all the settings once again after every few days.
I have set it to clear cache and everything at the closing of browser window, still the User Data goes on increasing few hundreds of MB.
The desktop version allows user to reduce the cache size but android FF doesn't seem to have any direct option.
Is there way to limit it through about:config or through any other way?
I don't use many add-ons; just 2 add-ons, AdBlockPlus and HTTPSEerywhere.
I am using Firefox 68.3.0


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How to read ext4 filesystem without mounting on a non-rooted device?
I perfectly know it is not possible to mount an ext4 partition from a USB key without root.
But in my case, I just need to read a password inside a .txt file (I don't have a PC right now and in the following weeks). This doesn t requires mounting it.
I know there's a Paragon plugin which allows acessing NTFS partitions without root inside Total Commander but it only works on exFAT and NTFS filesystems. But it proves it should be possible to do the same thing on ext4 without root.
So how to access my password right now without being able to root my device?

ext4 can be explored without mounting, using debugfs tool. But natively there is no way to access raw filesystem without root access on Android devices. Partitions are enumerated as block devices by Linux kernel, and default permission set by Android's init on block devices is 0600 (can be overridden in uevent.rc) or 0660 in case of vold, owned by 0:0. Also stock SELinux policy won't allow apps access files in /dev. So the block devices can't be read without root access.
Other way is to read a USB storage device in host mode through APIs. But Android's USB Host APIs provide only raw USB access, they don't have UMS filesystem code. However there are third party solutions like the one provided by Paragon, which includes raw-USB operations to achieve block-level device access, and the appropriate filesystem logic.
NTFS is a proprietary filesystem so it cannot have an open-source in-kernel Linux driver. Paragon develops drivers for filesystems including NTFS, exFAT (now open source) and HFS for Linux. They also develop exFAT/NTFS USB OTG host implementation for USB Mass Storage devices.
So what you are looking for is an app with third party implementation of USB OTG host APIs for ext4 filesystem. Paragon provides ext2/3/4 for Windows but no USB OTG solution is available for Android yet (probably because it's not of much use as ext filesystems are native to Linux/Android). However ExtFS support is part of Paragon's SDK for Android to be used by vendors and app developers. Also there's open-source Drive Mount (seems abandoned), which intends “to support HFS+ and Linux filesystems, sometime”.
As a side note, modded vold (such as vold-posix) is used on mostly custom ROMs which can mount ext4 partition from secondary external storage (SD cards, USB sticks) on non-rooted devices as well.

Paragon don t use thenfuse api at all on Android. This is true on pc but not Android. As stated in the question, I m not interested in accessing natively. completely wrong answer. Except of course if you know how to root from the device without using a third party computer.

@user2284570 correct. I haven't mentioned that either. "USB OTG host API" != "FUSE API". But I've edited to remove the word "FUSE" at all. Irrespective of that, what you need is an app with third party implementation of USB OTG host APIs for ext4, as already stated in my answer.


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My GKeyboard keeps crashing
It crashes every time I open my phone. I'm locked out of my device and I cannot even try to factory reset it.

it was a worldwide problem, latest update for gboard will fix it. if your device is standard configuration it will auto-update apps, in this case just enable Wi-Fi and wait for update.
if your device support usb otg connect a keyboard or mouse with usb-otg-adapter to unlock.
if you already unlocked you can speech-to-text in case you need enter text.
if you can't unlock your device, login to your google account and try to remote update gboard from pc by clicking this link. you can also remote install any other keyboard like swiftkey.
if nothing works you can adb sideload any official signed apk from recovery mode


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memory card as internal storage
My phone can't read my memory card and my memory card mounted as internal storage in marshmallow operating system. How can i get my data back?, in my setting it show memory 91 gb to 119gb but directory not exist, no data found all app that i run in my memory are gone. Some one please help me.

It could be that the memory card is defective. Have you tested it elsewhere?

i can't test because my device is linked with my memory card as internal storage. In my setting storage option my memory card show but not shows the data like app data etc..

Is it a removable microSD card? If so you can test it elsewhere and if it fails replace it. If not, take the phone to the nearest repair shop. It's that simple.

they format my memory card. My 91 gb data lost..

i know how to fix(root) but i don't know the process...

What process? If it was formatted the data is gone. The question now should be "does it work after being formatted?" If yes then keep using until it breaks; if not replace it. Your questions and your ramblings in comments doesn't make any sense.

my data is still in my memory card but i can't access.. that's all... and it's not formated.. it's shows 91gb but directory lost... so it can't find any data. that's all.

If it has become corrupted but not damaged then the solution is format or use a PC with specialized software to try to recover some of the data (very slim chance). That's ALL.

@Aman you can eject the SD card from settings and test it on some PC. Just don't format it. Then you can put the card back in phone. The bonding won't break until you don't "Forget" the SD card.

i use all the possibilities you mentioned but no data found....

i use many recovery software but nothing help me..

if your SD card is encrypted/adopted no external software will work. first thing i would do is make a snapshot with ddrescue for further analysis

As @alecxs mentioned, you cannot read SD card formatted as Adoptable storage on any other device. Connecting to PC is just to test if it's detected properly. If the point of your question is to recover data from Adoptable SD card, it's already been answered.

Duplicate of: How to decrypt Adopted Storage?

ya it detected properly but format option pop up..


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Gboard stopped working on Motorola phone
Gboard stopped working on Motorola phone - I cannot type as no keyboard appears  data amd cache say 0.
I have tried various methods suggested, but still no keyboard appears when a cursor appears in a text box.

https://android.stackexchange.com/questions/219482

Ok I have just fixed this on my Motorola phone.  I believe an update has been rolled out to solve the problem so the issue is, how to get your gboard updated if it hasn't happened automatically.
"Gboard stopped working" kept popping up on my screen while following through on the process below, so I had to keep selecting "ok" every time it popped up, giving me small windows in which to perform the necessary actions.
Go to the Play Store, search for Gboard (SEE BELOW) and identify the app (which had its icon next to the word in the search options that came up for me) and select it.  You should then have the option to update the app.  Select update.  After the installation finished everything was working again for me.
IMPORTANT To enter Gboard into the search bar you cannot use the keyboard.  So select the microphone at the right-hand end of the search bar and speak, "Gboard" - i.e. use voice to text.

Thanks for your help. To get to Gboard, I didn't have a microphone, but I was able to use the menu icon in the search bar which gave me the option of My apps & games. When I chose that, I was offered an opportunity to UPDATE Gboard, which I did. And, now it works.


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how apps bypass VPN?
I installed flipkart from apk. And without logging in searched for mobile phones.Then cleared app data and started VPN and then opened the app again but I was getting recommendations of searched phones. How flipkart bypassed VPN? How can we sure that browsers don't really bypass VPN?

Apps use device/OS identifiers to do profiling of you which don't change by using VPN or by clearing apps data.

It didn't bypass the VPN. The apps use your other identifications such as "Advertising ID" identify you. Then this information is used to give you suggestions/recommendations based on your previous browsing or search history.
Most apps will also keep a local cache. So, unless you have cleared data for the app, the app knows everything you previously did.


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Motorola G5 GBoard Issues
I've been having the same GBoard issues as a lot of other people , but I have been locked out of my phone because I powered it down and need to type in password to get into my phone. Any ideas as to how I should fix this issue??? I've have tried a cache partition wipe and it hasn't done anything. Thanks in advance to whoever finds a solution!

connect a keyboard or mouse with usb otg adapter

https://android.stackexchange.com/questions/219482


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RCS Messaging Encryption
With the launch of Google's RCS messaging protocol, is there any reason as to why it doesn't support end-to-end encryption, or is it a feature that they intend to implement at a later time?

is there any reason as to why it doesn't support end to end encryption, or is it a feature that they intend to implement at a later time?

RCS improves the old SMS by bringing modern features. It provides client to server side encryption but not provide end to end encryption.
According to What is RCS messaging? Everything you need to know about the SMS successor:

But Chat is missing one critical element: While the original RCS protocol allowed the implementation of client-to-server encryption, Chat does not offer end-to-end encryption like iMessage or Signal. Rather, it retains the same legal intercept standards as its SMS predecessor.

Asked about the privacy issues related to RCS, Google's product management director for Android Messages replied:

We fundamentally believe that communication, especially messaging, is highly personal and users have a right to privacy for their communications. And we’re fully committed to finding a solution for our users.

Google is working on it but no indication is given as to when end to end encryption will become a feature. In the meantime, when sending a message,

It's encrypted in transit, but it’s not fully end-to-end encrypted, so your RCS provider can potentially see the contents of your messages, and turn them over to the government if properly asked. Google says it will delete them from its servers as soon as they’re delivered to your phone

Like for SMSes, the providers will be able to read your messages until Google decides to implement end to end encryption.

The issue here is that RCS is not a Google product/service. Google serves RCS via a service called Chat, and Google Messages (the pre-installed, default SMS app on most Android phones) supports RCS. The Verge are pretty bad at conflating the two but even they say (emphasis added):

Google has been quietly corralling every major cellphone carrier on the planet into adopting technology to replace SMS. It’s going to be called “Chat,” and it’s based on a standard called the “Universal Profile for Rich Communication Services.”

But RCS is actually a "carrier-led" initiative organised by the GSM Association, which defines the "Universal Profile," and there are a lot of companies involved in supplying RCS products. Google has encouraged RCS, because it makes Android phones more appealing and competitive with iPhones and iMessage, but it doesn't "own" the initiative.
That means that RCS is actually provided by mobile operators, who are subject to legal intercept legislation. So when commentators say "Rich Communication Services is generally credited as being more secure" they are mainly talking about verified identities for businesses, which are supposed to reduce fraud. Because typically operators will need a point within their network where messages are unencrypted for when some law enforcement organisation requests access.


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Android Pie keep reinstalling Google Chrome even disabled
I've got Brave as my primary browser for my LG V30 (H93230d) running on Android Pie several months ago with Chrome disabled in my settings.
However recently I started to see Chrome appearing in my app drawer with latest version installed even it was previously disabled with Don't auto-update apps preference in Play Store.
I tried to disable it and force stop but the issue returns after several days. Any idea how to prevent Chrome to update/install automatically?

On a lot of devices Google Chrome provides the WebView implementation, which means that every app that displays HTML pages using the Android WebView system uses Chrome. Nowadays Google again prefers the
Android System WebView app to provide the WebView implementation but that is device specific and can be changed in the Developer settings.


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Full App Usage History
The procedure described here (code *#*#4636#*#*):
https://thegeekpage.com/view-app-history-android-even-someone-cleared/
worked fine in my phone. Is there another way to obtain a full log of each time an app was executed?
It could be a log-like history, with a chronological order with a timestamp and app executed (icon clicked). No need for CPU usage. A recent (~1 day) list would suffice.
Edit: my device is a Motorola Moto C Plus with Android 7.0.
Thanks.

See https://android.stackexchange.com/a/160177/131553

Thanks. Unfortunately the app mentioned there does not work on my device. I've edited the question to add my android version.

Plenty of apps on Play Store - search for "app usage tracker". This one is recently updated. Not tried by me https://play.google.com/store/apps/details?id=com.a0soft.gphone.uninstaller


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Is WiFi Calling possible over reverse tethering?
For internet access on my smartphone I use reverse tethering via USB from my PC while having it in flight mode. Everything works great (WhatsApp, Chrome, etc.) except calls, of course.
I was wondering if it would be possible to use "WiFi" calls without WiFi but with internet over reverse tethering via USB while the smartphone is in flight mode?

Why don't you try it with the setup that you have? You could get your answer very quickly.

Based on my understanding, isn't the technology called VoIP (Voice-over-IP)? So it shouldn't be necessarily using Wi-Fi, but anything that connects to the internet should work?

... and you just need to make sure that your router (and PC or whatever the hosts in between) isn't blocking ports used for VoIP calls.

Unfortunately, my current smartphone does not meet the necessary requirements (Android 7+), since it runs on Android 6 and there are no more updates probably because it is a Huawai. And before I buy a new one I would like to make sure that it works

Also I am not sure whether it is possible to turn on "WiFi" calls in the flight mode?


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start app automatically at reboot
I have an old-ish Google Pixel (gen1) phone that must have a hardware issue, and crashes/reboots every once in a while (every hour or so). It's unusable as a proper  phone but I thought I could reuse it as a single app kiosk-style screen. For example, I could have my Google Photo Albums displayed or I could use it as a stock ticker.
Is there a way to make a specific app start and take over the screen on reboot for Android?

I think my answer can be helpful. Just skip the step about splitting the screen.

Attempting to accomplish with automation. Using Automate to demonstrate how to do it:

Select the Broadcast Receive block. Click on it, in the Action section, select "Boot completed". Click Done.
Select App Start block. Click on it, in the Package section, select the first app you wish to start at boot. Click Done.
Save and give it a name. Link the blocks as seen on the image below.
In the Settings, select "Run on system startup".
Don't forget to give the necessary permissions when asked. Press start.

Every time you reboot your device, after the boot has been completed, the app will be launched.


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Is it safe to charge tablet from phone via OTG cable if tablet's adapter is 5.2V?
Is it safe to charge tablet from phone via OTG cable if tablet's adapter is 5.2V (a bit above)?

Your question does not make sense to me. Charging one device from another only works if both devices use USB-C and the power providing device supports USB power delivery. For USB-C there is no such thing as an OTG cable, just us an USB-C to USB-C cable with USB-PD support. And why you mention the tablet (charging) adapter is totally unclear to me as it is not relevant at all.

"Charging one device from another only works if both devices use USB-C" - thanks, didn't know that. I ordered LG V20 with extended battery and I have Lenovo Tab 10. As musician, I have a lot of screen on time because I use tablet as sheet music. So I want to be able to charge my tablet from LG V20 extended battery.

The LGv20 has a 3200 mAh battery and the Tab 10 one with 7000mAh. Charging the large battery using a much smaller one is not very effective. May be you should better look for a power bank.

I ordered this extended battery and I want to carry less things.

IDK maybe I need to cancel it and find phone with micro-usb type B

I just tried to charge my mom's C-Type Xiaomi Redmi Note 7 from Tablet and it works, why do you say it's not working? And C-Type OTG cable exists

The cable you have linked to is just a plain USB-C male to USB-A female cable. OTG is specific to micro USB ports (one special pin is used to identify if a cable is an regular or an OTG cable). For USB-C there are no such thing like an OTG cable. You can just use regular adapter cables and it works as you already have found out.

Is this cable fake? Because it says OTG. If yes, will mouse, keyboard and etc. still work with phone that supports OTG using this cable?

No it is not a fake - OTG of USB-C is just marketing nonsense. With USB-C there are no OTG cables anymore - or if you look at it from the other side every USB-C cable with an male USB-C plug and
a female connector at the other end can be considered an OTG cable.

Yes, as long as it is supported by the tablet and you have compatible cables available.
USB Standards specify that charging voltage should be 5.00V ± 0.25V, i.e. 4.75V~5.25V.
Upper limit is 5.25V which is higher than tablet adapter voltage ; add to this the resistance offered by the cable and the input voltage will be well within safety limits.
How efficient it would be is upto you to verify as Robert pointed out in comments

Thank you for answer! Another thing: if I charge like that, will I lose almost 50% of energy. Because when energy goes from battery to cable it loses ~25% and after that when goes to another battery will I lose another ~25%?

Cable losses are not so high as you suspect. You can buy a good cable. For help see this answer.  How much over all loss you would have needs to be tested by you. That said, power bank is a better option as suggested by Robert

I don't really understand why power bank is better option if I will have 10500mAh battery for my phone. Anyway, is loss by charging using phone will be higher than using powerbank?

From your answer I understand that cable thickness matters.

yes............

Is it possible to know AWG of my current cables?

So, if I want to use 1A charger without more loss than USB standards and with transfering function, it has to be 15cm long (AWG 28)?

Sorry,busy so can't verify what you are claiming but please re-read and if you still have a question ask a separate question linking that answer as background. you can know the AWG either through documentation or physical measurement or ask somebody who deals in cables

Ok, thanks for help.

Simply put go in for long, thick cable. Sample link is provided in that answer


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App not installed. This app isn't compatible with your phone
Rooted my Tecno Spark K7 Android 7.0 Nougat (Stock ROM + Magisk + TWRP). Trying to reinstall my apps from backup apks but I'm getting this message App not installed. This app isn't compatible with your phone. Doesn't really make sense to me, since I'm using the same apks that were installed on the same phone with the same stock ROM.
Only difference is the rooting but my old phone was also rooted, and I had no trouble reinstalling its apps, so I honestly don't see how rooting is the cause of my current issue.
How do I solve this?

install from Google Play, or copy files into /data/app/-1/base.apk and chown 1000.1000

@alecxs, I'm going to try that and see how it goes. Thanks.


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Which Android spin-off can I use for the possible maximum privacy?
Complete mobile phone privacy is a near impossible feat, but I would like to have as much privacy as one can have.
Which smartphone OS or version can get me close enough, while allowing for dependable functionality?

You can check out GrapheneOS (successor of Copperhead OS). However it does not support a lot of devices.

Thanks, going to check it out.

samsung knox is a good mainstream alternative


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How to Make Samsung Galaxy S10e perform IR?
Now, I know the Samsung Galaxy S10e does not have a built-in IR blaster.
However, the comment at the end of this post says the built-in iris scanner has some sort of IR capability?
Is that true, and do you think it's possible to utilize that?
Otherwise, I would use one of those IR remote control apps on Google Play and I'd need an IR blaster attachment like this.  But is this the best way to go?
I'm thinking to control random TVs in hotel and airport lobbies... (just for fun) or the AC at a friend's house or our Stereo receiver we have.


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Is it possible to clone phone to anohter phone with same model using TWRP?
I have Samsung S7 and I have made whole backup of it to my sdcard - system, data, chache, etc. One day that phone broke and I am going to buy new one with same model. Will it work if I restore backup from sdcard to a new phone? I don't know if the new phone have same ROM, but if it needed then I can install it because I still have it on my computer.

It should work as long as both phones have identical OS versions. Two points 1. Take care not to restore EFS and other partitions that are device specific 2. Restoring data should be enough. I had done a similar thing with two note 2 devices way back. I won't make this an answer because I am not aware of latest Samsung things but in principle, no problem

If the backup of the user data partition in decrypted or encrypted format? As the device encryption usually uses hardware based encryption cloning the user data partition in encrypted form should not work. If it is decrypted and you restore it the system may be confused as it expects an encrypted partition. But those are just theoretical thoughts, I don't have any practical experience with closing partitions.

@Robert very valid point. Didn't consider that

Disk dump of encrypted partition is problematic but TWRP backs up decrypted userdata partition using tar (or we can do from commandline if TWRP is able to decrypt FDE/FBE). But the hardware-specific things are more trouble e.g. the databases which contain IMEI or other identifiers need to be updated. Similarly things dependent on TEE cannot be backed up e.g. fingerprint. Better is to just back up the selective things like settings, apps data, personal data etc.

just prepare your current phone to be ready creating a fresh backup via adb shell for the day the screen will be broken


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Is data transfer from a Pixel 3a XL possible via USB 3?
The Google Pixel 3a XL has a USB C port.
Is it possible to connect it to a computer that only has a USB 3 port to transfer data between the computer and the Pixel 3a XL?

According to GSM arena the Google Pixel 3a has an USB 2.0 type-C connector.
Note that the USB transfer speed is independent of the used USB connector type.
Therefore USB 3.0 is not supported by the Pixel 3a - you can only use USB 2.0 connections for data transfer.

Thanks Robert.  Even though USB 3.0 is not supported, it should still be able to transfer data (backwards compatible) via a USB 3.0 port, correct?

@RockPaperLizard Of course you can do this. Every USB 3.0/3.1/3.2 port can be used with USB 2.0 and even USB 1.1 devices.

Great. That's my understanding as well.


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How to downgrade from Android 9 to Android 8 or Android 7 on LG V20?
I am using LG V20, model number is LG-F800K. 2 days ago, I installed the official update to Android 9. However after the update, my phone became battery drained faster and worked slower than before. I have tried at least the following 3 ways to try to get back to Android 7 or Android 8:

https://forum.xda-developers.com/v20/how-to/guide-lg-v20-to-life-t3827732 -> "Download failed" error.
https://lg-firmwares.com/how-to-flash/#how-to-flash-new -> Unknown model.
https://lg-firmwares.com/how-to-flash/#how-to-flash-old -> Error "could not connect to server".

As of now, I really don't know how to reduce the Android version on this device?
I would appreciate your help.

afaik unlocking bootloader will let you by-pass anti rollback protection, but this requires a factory reset

I have downgraded the version successfully. You need to use LGUP DualMode in this case, it will help identify your device!
You can download it here (Copyright © by TecKnight): LGUP_DualMode.zip

What is your connection to this download? Are you the developer, creator, or owner for it? Should there be a disclaimer of personal interest here?

@wbogacz It works on computers, you just need to plug your phone, via USB cable into download mode, it is recoverable.
That software was given to me by a foreign friend who works at an LG store, I added copyright information based on the upload account name because I didn't know exactly who was the owner of it.


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Facebook Messenger keeps on playing sound in notification
I'm using facebook Messenger on a Samsung Galaxy S9. Since a few months now, Messenger keeps on playing a notification sound when receiving chat messages even when I change the sound to Silent.
Let's be precise :

When going in Messenger parameters and choosing a notification sound, there is no "silent" sound (and I'm pretty sure it existed before)
When going into "Manage notification" from the app which leads to the notification management of the OS, I can chose "silent" as a sound but after a while (1/2 hours or so, sometimes less), messenger changes it back automatically to its default sound.

That's driving me crazy. I want to keep notification as I used to : vibration, preview but no sound.
I tried to delete and reinstall the app, nothing has changed. I even left a message in the Play store.
Any idea ? Thanks

Have you found a way to make the change permanently. I have the same problem here with my Moto G4 and my new Galaxy A50. I want to keep the vibration so I have to select "Silent" for the sound but it always come back to the messenger sound.

Unfortunately I gave up. I chose silent. At least it doesn't ring. But I can't have the vibration either


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Install arbitrary apk from filesystem on Android 10?
Looks like in Android 10, "install from unknown sources" was changed from a global setting to a per-app permission. Apparently in order to install APKs now I need to whitelist each app that I'm trying to do this from. However, none of the apps I actually need to do this from (default system "Files" browser and Root Browser) even have this setting. Root Browser has a context menu to open with Package Installer but it doesn't work?
Do I need to get another third-party app just to install APKs from the filesystem? This is so lame. Thanks.
Edit: I am on a Pixel 3 running stock Android 10.0.

To disable /enable this permission :
Settings → notifications→ Special app access→
 Install unknown apps →your app
AFAIR, this change came about from Oreo (Android 8)
Solid explorer and Mixplorer are the one's I use and they both install apk's (OnePlus 7, Android 10)

(From Mixplorer - click to enlarge)

I know that, but my issue is that none of my Filesystem browser apps including the system one show up in this list (even with system apps set to show) or have the permission available in their system app info screens. Do you know of any file browser apps that can install APKs?

@Eliot you can also try granting permission to your file explorer apps from CLI using appops: https://android.stackexchange.com/a/216092/218526


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Is there a way to Modify Recovery Menu Options?
Hi guys I am setting up an android system for a company, one of the requirements is that "employees can't factory reset/ wipe out data of a device". I have already done the proper implementations on the OS itself. however I was looking throught the recovery.img and boot.img files to see if I could modify any xml file or anything to hide or set password auth for the factory reset and wipe options from the recovery. I know a guy with knowledge would be able to activate it back, however the average employee barely knows what recovery is, so it's really unlikely.
It does not matter what type of recovery is needed to achieve this whether its an stock recovery or a twrp or cwm one. any ideas?

for custom recovery you probably have to unlock bootloader - which will open a backdoor for boot/flash/format/erase partitions from fastboot. better stay at stock recovery, enable FRP, enable cloud

it's possible to place a file in /cache partition which does factory reset, maybe you can place a command --just_exit which may disable recovery completely https://android.googlesource.com/platform/bootable/recovery/+/master/recovery.cpp

Oh thanks, Ok so, as I can tell, each function requested by the user such a "factory reset" creates a file with a command on the cache/recovery/command folder, however how should I store the file there as a just_exit entry? what file extension does it have? are those commands in a c# stuff as well?

so by removing the recovery partition the user won't be able to even access the menu right?

You can flash boot.img to recovery partition so that device always boots to normal OS. But all that it takes to boot into recovery mode is fastboot boot recovery.img if the user knows even the basics. An advanced way could be to modify bootloader so that it never boots from recovery partition. But it requires hacking closed-source bootloader binary and is very device-specific. Another idea is to define an init service which creates /cache/recovery/command file (as @alecxs mentioned) on every boot/shutdown. But I never tried this and it's also not hard to bypass with some knowledge.

flashing boot into recovery is worth a try, maybe there is a little chance the bootchain will detect it as (signed) stock image and allows to continue booting with (re-)locked bootloader


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Un-register service from hwservicemanager
I have disabled the fingerprint sensor on my phone by setting the device tree node status to disabled. When I boot up, the fingerprint menu options are gone, but dmesg shows that hwservicemanager is trying to start a fingerprint sensor over and over, but init can't find the service:
[  625.488742] init: Could not find 'android.hardware.biometrics.fingerprint@2.1::IBiometricsFingerprint/default' for ctl.interface_start
[  625.502583] init: Received control message 'interface_start' for 'android.hardware.biometrics.fingerprint@2.1::IBiometricsFingerprint/default' from pid: 669 (/system/bin/hwservicemanager)
[  625.502658] init: Could not find 'android.hardware.biometrics.fingerprint@2.1::IBiometricsFingerprint/default' for ctl.interface_start
[  625.523352] init: Received control message 'interface_start' for 'android.hardware.biometrics.fingerprint@2.1::IBiometricsFingerprint/default' from pid: 669 (/system/bin/hwservicemanager)
[  625.523427] init: Could not find 'android.hardware.biometrics.fingerprint@2.1::IBiometricsFingerprint/default' for ctl.interface_start
[  625.538080] init: Received control message 'interface_start' for 'android.hardware.biometrics.fingerprint@2.1::IBiometricsFingerprint/default' from pid: 669 (/system/bin/hwservicemanager)
[  625.538545] init: Could not find 'android.hardware.biometrics.fingerprint@2.1::IBiometricsFingerprint/default' for ctl.interface_start

How do I tell hwservicemanager to stop trying to start this now non-existent service? I saw here that there is an option to remove the hidl definitions from a manifest file, but I would like to enable or disable the fingerprint sensor at runtime. I can enable and disable the service with start vendor.fps_hal and stop vendor.fps_hal, but I can't stop hwservicemanager from trying to start it.

You can check system/hwservicemanager/ServiceManager.cpp to see when and why hwservicemanager is setting ctl.interface_start to trigger init to start the HAL service.
Unless you are willing to update system/hwservicemanager/ServiceManager.cpp, I don't see a way to achieve what you are trying to do.


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Android automatically deletes content of my Downloads folder
Previously I had a Nokia 7.1 (Android 9) when I started to notice this issue. Every few time, the older images I had on my Download folder disappeared without I doing nothing. From time to time it happened again. I let this pass. Every time that ocurred, I manually download the images again, because I needed to have those images there.
Today, I have another smartphone (Multilaser MS50X, a brazilian cellphone with Android 8.1) and exactly after a month of started using it, the older images of my Download folder disappeared again!!!
I've checked some apps that I think it could be doing something like that:
* Google Chrome (downloads data to this folder)
* Google Photos (sync and backup images)
* File Manager + (access to data and folders)
* Quickpic (gallery app)
But no one have an option to "automatically delete Download folders content after a while".
I don't have any Clean App, neither use the function "Free up space" of Android. Also none of those cellphones had an option like "storage booster" or "smart storage" like state on this thread: Android phone automatically deletes photos?
Any clue where can I look? It's annoying
Regards
Update: When I open Google Photos, go to 'Photos on device', and select 'Download', I can see all the deleted images (the images that should be on that folder and it doesn't)

https://android.stackexchange.com/search?q=%22Google+photos%22+%22delete%22+%22photos%22

Google photos has a setting for "free up free storage". Check if that's enabled

Also some cloud backup apps have a similar option to free up device space

Check if you have storage manager enabled. It will automatically start deleting backed up photos and videos after they cross the selected timeline.
You can locate it in Settings > Storage > Internal Storage > Storage Manager.


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Google assistant found a bill I need to pay from my email but I've lost the notification. Where can I find the full list?
On my pixel there's an app called "google". From there, More -> Settings -> Notifications -> Bills. I can toggle this option on and off but can't find a list of bills it actually found. Is this available somewhere?
The obvious answer is to go trawling through gmail, but I'd like to recover the specific notification and see what google found.

If you open the "Google" app and select "Updates" button(?) at the bottom it will show you the personalization page: weather, appointments, stock prices, etc. Your bill may show up therein.

You can try Nova launcher method - https://www.theandroidsoul.com/recovery-lost-and-cleared-notifications/

Does this answer your question? Notification messages from when I turned on the phone. Where are they?

Useful ideas. Thanks all! @MorrisonChang the updates section sounded promising but all it's showing me is I have an empty calendar.


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Where can I see the file format of my SD card on Android?
Where can I see the  file format of my SD card on Android?
I use a Samsung Galaxy s9 with Android 9.

Note a dupe because here we're talking about SD cards.


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How to flash android AOSP 10 to device?
I used to run Android AOSP 6.1 on my Nexus 5 by manually flashing the boot, cache, system, userdata, recovery images one by one using fastboot. I managed to successfully flash Android 6.1 on my Nexus 5 following this tutorial https://www.youtube.com/watch?v=m5BMfvO9Xi0
I have managed to build Android AOSP 10 and my goal is to flash it to my Pixel 2. First thing I noticed is that the output dir looks a bit different now. There are a few different images and there is no more recovery.img. The Android 10 Factory 10 dir contains this images:

I tried to manually flash the boot, dtbo, system_other, system, vbmeta & vendor images but the device ends up in a boot loop.
Does anyone know how to flash the Android 10 AOSP images to a device?
Thank you in advance!

The recovery is now built into the boot image instead of having a separate partition. So, a separate recovery image does not exist.
The files you have are supposed to be flashed to their respective partitions:
Boot to boot,
System to system,
Vendor to vendor,
Vbmeta to vbmeta,
Dtbo to dtbo
You can avoid the system_other as it is to build a dummy into your inactive boot slot. It isn't actually used. But if you want, you can flash it to the inactive slot. You check current active slot by using this command: fastboot getvar current-slot. Then flash to that slot by adding the slot suffix (example: If current slot is a, flash it to b - fastboot flash system_b system_other.img
Remember that you need to perform a wipe of internal storage from either fastboot (fastboot -w) or by going into the Android Recovery mode.