Nexus 5x stuck in download mode after flashing I flashed my nexus 5x following the instructions from the official android website https://developers.google.com/android/images . I installed fastboot on my Ubuntu 16.04 and started flashing. After executing the script flash-all.sh, it indicates that the phone was properly flashed in terminal, and even my phone shows commands that the firmware is getting installed. But after the end of the flash, my phone reboot and get stuck on a the message :
Firmware Update
Do not unplug the USB connection until the process is complete

with a progress bar stuck at 0%.
I've tried flashing with the firmwares : 6.0.0 (MDA89E), 7.0.0 (NRD90M), 7.1.1 (NMF26F, Dec 2016). And with every firmware I get stuck after the flashing ends.
Note
When I visited a link given by sancho.s , I noticed that I can't get into recovery mode, my phone get stuck into the same Firmware Update screen unstead.
There was no specific question posted, so I asume you have your phone bricked (unusable) now, and you want to get it out of that state.
Here you find a few alternatives:


Two people reported here that unplugging the cable, then holding the power button down restarts the phone, and it likely brings it back to life. Similarly here... And there are plenty of similar posts around.
You commented that this does not work.
There are further instructions here.
From here: 
"If a battery pull doesn't fix the problem, turn your phone off, charge the battery sufficiently (while it's off) and then unplug from the charger. Hold Volume Down and Power to enter HBoot and enter recovery. Once you see the error symbol pull the battery out again and then reinsert the battery and start as normal. This (for some reason) works for a lot of people. If all else fails enter recovery and do a factory reset."