Thanks. Upgrading to RC and then downgrading to stable (OTA-8) worked.

Now in the battery dropdown settings the flashlight button works. That didn't work with the OS version it shipped with. The new automatic brightness is also nice.

I guess I'll mark this as solved even though going through RC is more of a workaround than an actual solution, because the update really should just work.

I got Volla Quintus with Ubuntu Touch today and naturally wanted to install the latest updates straight away. But the “Ubuntu touch” “version 3” update fails.

See screenshot for error message. I think umount: /dev/block/dm-1: Invalid argument or /dev/block/dm-1 has unsupported feature(s): FEATURE_C12 will be the problem. Maybe e2fsck in the recovery/update installer is older than the one that created the the Ubuntu Touch file system?

What is the best way to solve this? Is it possible to simply deactivate the “FEATURE_C12” in the live ubuntu touch system before the update and/or does this have any negative effects? I only found that if you do it with tune2fs -O ^orphan_file the filesystem needs to be unmounted. I'm new to ubuntu touch, not sure how I would do that.