Where does twrp keep the internal storage backed up? I have chosen to backup everything and all extra partitions on my twrp backup. When browsing the twrp backup folder, I renamed the .win extentions to .tar and unziped them using linux but I cannot find where twrp keep the internal storage contents. eg. emulated/0/
TWRP does not backup internal storage, like your photos, videos, music, ebooks, etc. (things in /data/media), that is why you can't find it.
As noted in the TWRP's FAQ from their official website:

Creating a backup of the user data partition will NOT include
/data/media (your internal storage)! That means if you save photos or
data on the internal storage (e.g. some apps will save data there as
well) those will be NOT included in a TWRP backup! There are many
people thinking that this is the case but due to a decision taken by
the dev team this is the current way of how it works.
To be absolutely clear when you do something like this:

Creating a full backup in TWRP (including /data partition)
Factory resetting your phone
Restoring your previously taken full backup
Result: all your saved data will be there but your data on the internal storage gets LOST!



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