[Thinkpad Tablet Android Development] uschipower:
I think i found the problem. After the tip of alecxs about dm-verity, I used this zip:

[Deprecated] Universal DM-Verity, ForceEncrypt, Disk Quota Disabler [11/2/2020]

Hi all! For the past couple of months, I've been looking into making a more universal solution to disable dm-verity and forceencrypt. Needing to take different zips, modify them for different devices, and then cross your fingers when you switch...

xdaforums.com

Although the zip is deprecated and 3 years old, it seems that it still works

the functions of the zip are controlled via filename.

First i flashed the zip with twrp with filename dm-verity.zip to disable dm-verity only

Result: TWRP-Recovery is not replaced with StockRecovery, but after restoring data-partition, device cannot boot into system as described above.

Second try:

starting from beginning, with clean stockrom via LRSA + flashing TWRP + format data-partition + reboot in recovery as described in thread of zip file

installing the zip-file with filename dm-verity_fec_quota.zip. By this encryption was disabled additionally together with disabling dm-verity.

Then boot into system and have a look in settings -> System is saying "device not encrypted"

I restored data partition from twrp backup and device can now boot into system.

Remember, the backup was made with encryted data partition.

My conclusion:

This TWRP can read/backup from encrypted data-partitions, but cannot write on encryted data-partition.

It also seems that twrp doent write partition as image image/partitions. It seem that twrp only

- write files

- can write on unencrypted partitions

My questions:

- can every twrp only write on unencrypted partitions? What about the TWRP in this thread?

- I read this too: https://twrp.me/faq/whattobackup.html

...On most of these devices, you will see an option on the backup page for System Image. A system image backup takes up more space than a regular system backup, but the system image backup is a bit-perfect backup that, when restored, will not break dm-verity

I do not find such an option in this twrp in this thread here.

Please explain.

I had a look with filemanager of twrp into /system/, but there is no file recovery-from-boot.p

Could you please explain this?

I also made many thoughts about this too:

What i do not understand:

So, on non-rooted devices, every app, every app-setting and all generated data are only on data-partition, right?

Apps can also write on data-partition, right?

Most of all backup-tools can only backup the apps itself but not the app-settings.

Additionally only a few apps write their settings to /data/media so that you could backup the settings by coping files manually.

Why do / cannot Apps backup everything on data-partition?

On the other hand, there are apps like NANDroid Backup or Helium which promise this, but they need root.

Whould you be so kindly and explain this?

So, my conclusion is:

- with twrp-backup, it is only usefull for restoring data-partition, right?

- with twrp, you can only restore on the same rom, right? So it is adviced to backup the original romfiles itself too?

At https://twrp.me/faq/whattobackup.html:

...system, data, and boot. For most cases, this is sufficient for backing up a ROM...

According to you, it is better not to restore system- and boot-partition from twrp-backup, but it is better to install them via rom-installation and restore only data-partition?

How do this fit to this: Many articles describe TWRP as backup tool when you want to test different roms. You make a backup, install a different rom, and if you are not satisfied, you restore the backup and you are at the same point of origin when you made the backup (complete rom + data + every settings!!!)

According to you, this is not possible.

Could you please explain your position

ok, i understand this, it is comprehensible.

Now, the following situation: You have a tb-x505f with Android 10.

Then, you buy a new device running Android 13. On old device, you have installed many apps, from different stores and manually via apk-file.

You have configured the apps. only a few apps have an integrated export/import for their settings.

you want the same apps and the same app-configs on the new Android 13 device- of course without installing and configuring the apps again.

You also want to have the config of android itself on the new device (wifi-passwords, certs in androids cert-storage, gui-config, google-accounts and other accounts, etc)

what is the correct way to do this?

According to your explanations, twrp is not the right way.

Remember, i have in my mind that you said that everything is stored on data-partitions

Thanks.