Flashed this version today. Worked fine this time even the method is quite time consuming. But today I wrote down some notes what I did, which fit to my settings and my level of knowledge. I hope this will help me to speed up the next update.
For those who are interested …
My facts:
- FP Open
- no Gapps
- Xposed (XPrivacy is the only module I use)
- AFwall+
- currently not encrypted as I would like to use Snooperstopper again and I’m afraid that I will run into this issue again.
My update notes:
-
Backup backup backup … oandbackup (app+data) of all apps + TWRP Backup before doing anything. Just to prevent data loss if something goes wrong while the update
-
Download latest manual.zip: https://code.fairphone.com/projects/fp-osos/user/fairphone-open-source-os-installation-instructions.html
-
unzip and remove that the recovery.img flash part, that it will not be flashed to an eventually older/outdated TWRP recovery version: ✏[HOWTO] Upgrade FPOOS without overwriting TWRP (don’t forget to delete the recovery.img from images folder, remove it from SHA256SUMS and MD5SUMS files as well and replace the checksums of the flash-for-unix.sh [make it executable in advance] with the new generated checksums)
-
Flash procedure itself:
-Prepare like described above
-Go offline (disable WLAN and mobile data) and disable xposed framework and afwall+ (optional but maybe safer) → reboot
-Boot into fastboot e.g. via „adb reboot bootloader“
or
turn it off and use the hardware buttons → press „power Button + Volume Down“ (test connection via „fastboot devices“)
-Flash the update via „flash-for-unix.sh“ (it should not flash a maybe outdated TWRP revocery.img after the preparation under point 3 - this is more important when the device is encrypted, but maybe Fairphone added a newer TWRP in the meanwhile, not sure)
-Boot into TWRP recovery → press „power Button + Volume Up“ for some seconds
-Flash latest version of all modifications you use (here xposed framework + fdroid privileged extension)
-Reboot to system.
Notes which might be interesting if parts of the procedure are not clear anymore:
- http://dl-xda.xposed.info/framework/sdk23/arm/ (xposed framework)
- https://forum.xda-developers.com/showthread.php?t=3034811 (xposed installer)
- https://f-droid.org/packages/org.fdroid.fdroid.privileged.ota/ or https://f-droid.org/repo/org.fdroid.fdroid.privileged.ota_2070.zip (F-Droid privileged extension)
- https://forum.xda-developers.com/android/software/guide-installing-adb-fastboot-linux-adb-t34786781 or ✏ Installing Fairphone Open OS using Fastboot (Step-by-step Guide) (plugdev group configuration)
- ✏ Installing Fairphone Open OS using Fastboot (Step-by-step Guide) (fastboot flash method wiki note in general)
Thanks to all who provides a note listed above. This really helps. 
@StephanK, @freibadschwimmer, @random, …