Pumpino said:

I'm thinking of getting a Pixel 5 and flashing LOS 20 on it. Based on reading the above posts, am I correct in thinking that official TWRP 3.7 won't successfully boot or create backups of any Android 13 ROM, whether it's stock or custom? Without wanting to sound rude, what's the point of it then?

I have a Pixel 4a 5G and there's no official (or working) TWRP. I'm surprised that two ROM friendly phones don't have working versions of TWRP. Is there something challenging about these models for devs?

The phones are ROM-friendly, but as Google keeps releasing newer Android versions, the OS's themselves keep getting less friendly with regard to modding.

Quite often, a new OS release requires TWRP developers to make changes to accomodate Google's OS "improvements". That can take time.

HippoMan said:

The phones are ROM-friendly, but as Google keeps releasing newer Android versions, the OS's themselves keep getting less friendly with regard to modding.

Quite often, a new OS release requires TWRP developers to make changes to accomodate Google's OS "improvements". That can take time.

Yes, but TWRP 3.7 was released in October last year. It flashes, backs up and restores ROMs fine with Android 13 on my Mi 9T Pro. Is there something about the Pixel 4a, 5 and 5a, such as the chip or partition layouts, that make them more challenging?

Pumpino said:

Yes, but TWRP 3.7 was released in October last year. It flashes, backs up and restores ROMs fine with Android 13 on my Mi 9T Pro. Is there something about the Pixel 4a, 5 and 5a, such as the chip or partition layouts, that make them more challenging?

Even though the Mi 9T Pro version of TWRP is numbered 3.7, that doesn't mean that the Pixel 5 version of TWRP that is numbered 3.7 is the exact, same software. TWRP builds are device-specific, and it's no doubt a different build for the two devices. The over-all feature set of the 3.7 versions is generally the same among various devices, but the lower-level implementations can be very different between TWRP's that are intended for different devices. This could indeed be due to chip or partition layouts, as well as other factors.

When Google releases a new OS version, there is no reason to assume that a TWRP version for an earlier OS release will work flawlessly under that new OS version.

Google obviously changed some things in Android 13 for the Pixel 5 which make last October's Pixel 5 TWRP version unrunnable under Android 13 on that device. And I believe that there have been upgrades of Pixel 5 Android 13 since that OS version was first released for that device.

Hopefully, the TWRP developers will get this sorted out with a newer TWRP version for redfin (Pixel 5) that works with the latest Android 13 version on that device. Just keep in mind that these TWRP developers are unpaid volunteers.

PS: And unfortunately, Google has developed a reputation for making it more and more difficult to mod devices as the Android versions increase. Since the device (Pixel 5) and the OS (Android 13) are both developed by Google, the chances of *any* implementation of TWRP working properly on that (and any other) Google-built phone will continue to diminish even more quickly as newer Android OS's are released.

Pumpino said:

Yes, but TWRP 3.7 was released in October last year. It flashes, backs up and restores ROMs fine with Android 13 on my Mi 9T Pro. Is there something about the Pixel 4a, 5 and 5a, such as the chip or partition layouts, that make them more challenging?

most of the twrp device versions that i took a look on twrp official site ar from october.lets wait and se when android 14 and custom roms support android 14 and twrp next release.i suspect that there wil b an updated version of twrp for all the devices that are supported on their site officially.

_euphonic_ said:

How can I instal TWRP on Pixel 5 (unlocked bootloader)??
I've got some errors

And what differences is between slot A or B?

AFAIK, T.W.R.P has not release an Android 13 version for the Google Pixel 5:
a. TWRP 3.7.0 Released
b. TWRP for redfin

_euphonic_ said:

How can I instal TWRP on Pixel 5 (unlocked bootloader)??
I've got some errors
Why it is "not allowed to flash recovery"
And what differences is between slot A or B?

Pixels do not have a recovery partition. The recovery kernel is compressed and lives in the boot image. Because TWRP does not support compression, it cannot be installed. If the TWRP image is written to /boot, it will overwrite the system kernel, resulting in a device that will only boot to TWRP, until the original boot image is reflashed.

The proper way to use TWRP on a Pixel is live boot: fastboot boot twrp.img

This tells the device to load TWRP into memory so that the user may perform desired functions; upon reboot, the device will boot normally.

However, most flashing operations can be performed by ADB from bootloader or fastbootd, obviating the need for a custom recovery

The A/B slot scheme is for seamless system updates. This allows the device to update "on the fly" without extended downtime.

The legacy method with a dedicated recovery partition (e.g., Samsung) requires the device to reboot into recovery to update the system, as the system cannot be updated while running. Having two slots eliminates this problem, as follows:

1. Pixel is running on one slot, let's say it's slot A with the July update.
2. When the August update becomes available, the device downloads, unpacks, and installs the update to the B slot
3. When installation is complete the device then reboots to the updated slot, in this case slot B, booting into the August update. Upon successful boot the B slot is marked as valid, and the device will continue to boot from that slot after every reboot.
4. When the next update (September) becomes available, the process starts over again - while running on slot B, the system downloads and installs the update to slot A.
5. If at any point the updated slot fails to boot, the device will revert back to the original slot.

• OTA updates can occur while the system is running, without interrupting the user. Users can continue to use their devices during an OTA—the only downtime during an update is when the device reboots into the updated disk partition.
• After an update, rebooting takes no longer than a regular reboot.
• If an OTA fails to apply (for example, because of a bad flash), the user will not be affected. The user will continue to run the old OS, and the client is free to re-attempt the update.
• If an OTA update is applied but fails to boot, the device will reboot back into the old partition and remains usable. The client is free to re-attempt the update.
• Any errors (such as I/O errors) affect only the unused partition set and can be retried. Such errors also become less likely because the I/O load is deliberately low to avoid degrading the user experience.
• Updates can be streamed to A/B devices, removing the need to download the package before installing it. Streaming means it's not necessary for the user to have enough free space to store the update package on /data or /cache.
• The cache partition is no longer used to store OTA update packages, so there is no need to ensure that the cache partition is large enough for future updates.
• dm-verity guarantees a device will boot an uncorrupted image. If a device doesn't boot due to a bad OTA or dm-verity issue, the device can reboot into an old image. (Android Verified Boot does not require A/B updates.)

Click to expand...

Contrast this with legacy A only devices (like the aforementioned Samsung) where:

• Updates can only be installed in recovery, requiring extended interruption of user activities; the device cannot be used during the update
• Updating can take quite some time, 5-10 minutes or more
• If an OTA update fails to apply, the device will fail to boot
• If an OTA update is applied but fails to boot, the device is unusable until manually reflashed
• Any errors will result in update failure, which may cause the device to fail to boot
• Updates have to be downloaded entirely, then unpacked and installed by recovery kernel, which requires free storage space
• The update must be held in cache until the device is updated, taking up space
• If the boot image is corrupted, the device will fail to boot

V0latyle said:

Pixels do not have a recovery partition. The recovery kernel is compressed and lives in the boot image. Because TWRP does not support compression, it cannot be installed. If the TWRP image is written to /boot, it will overwrite the system kernel, resulting in a device that will only boot to TWRP, until the original boot image is reflashed.

The proper way to use TWRP on a Pixel is live boot: fastboot boot twrp.img

This tells the device to load TWRP into memory so that the user may perform desired functions; upon reboot, the device will boot normally.

Thank you very much for the explanation. It helped me understand a lot.
I do exactly as you wrote: "fastboot boot twrp.img" and Latest TWRP hangs me at the introductory logo screen.
Only one of the earlier versions works properly.

In fact, it doesn't quite work properly when I try to mount
/system - in the manager I can't change values, grant permissions or delete
/storage - shows nothing, no content, shows 0MB

Another thing...
how can I make a backup using ADB or FASTBOOT and how can I restore it?
What are the commands.

Thank You