@NeoTheThird Neo, do you have any news or do you need anything else from us?
Best regards,
kkr

@simon Well, then at least its not the fault of my phone! Your comment about the sound is interesting because mine does not produce any sounds at all.

Update: I tried to do the steps from the magic-device-tool manually. Using the lineageos recovery image I was at least able to push the .tar.xz files with ubuntu-device-flash to the cache folder. But ubuntu-device-flash does not continue after pushing the files without giving any comment. Adding -v does not change the output.
Does anyone have any ideas how to continue?
Regards

@NeoTheThird Yes I did, this does not seem to imply recovery mode. I seems like abd must be enabled persistently in build.prop. I was able to get some logs this way but the content was not satisfying so I tried again to install ubuntu. After doing so, i pushed the current LineageOS recovery image (the one z3ntu published in https://forum.fairphone.com/t/flashing-lineageos-is-not-working/31584).

Finally, here are the logs
The logs you wanted:
1.) cat fstab.qcom:
There is no such file as fstab.qcom. Instead, there are fstab.ranchu and fstab.goldfish
They contain the following:

~ # cat fstab.goldfish
# Android fstab file.
#<src> <mnt_point> <type> <mnt_flags and options> <fs_mgr_flags>
# The filesystem that contains the filesystem checker binary (typically /system) cannot
# specify MF_CHECK, and must come before any filesystems that do specify MF_CHECK
/dev/block/mtdblock0 /system ext4 ro,barrier=1 wait
/dev/block/mtdblock1 /data ext4 noatime,nosuid,nodev,barrier=1,nomblk_io_submit wait,check
/dev/block/mtdblock2 /cache ext4 noatime,nosuid,nodev wait,check
/devices/platform/goldfish_mmc.0* auto auto defaults voldmanaged=sdcard:auto,noemulatedsd

~ # cat fstab.goldfish
# Android fstab file.
#<src> <mnt_point> <type> <mnt_flags and options> <fs_mgr_flags>
# The filesystem that contains the filesystem checker binary (typically /system) cannot
# specify MF_CHECK, and must come before any filesystems that do specify MF_CHECK
/dev/block/mtdblock0 /system ext4 ro,barrier=1 wait
/dev/block/mtdblock1 /data ext4 noatime,nosuid,nodev,barrier=1,nomblk_io_submit wait,check
/dev/block/mtdblock2 /cache ext4 noatime,nosuid,nodev wait,check
/devices/platform/goldfish_mmc.0* auto auto defaults voldmanaged=sdcard:auto,noemulatedsd

2.) File system
~ # df -h
Filesystem Size Used Available Use% Mounted on
tmpfs 923.1M 20.0K 923.1M 0% /dev
tmpfs 923.1M 16.0K 923.1M 0% /tmp
/dev/block/mmcblk0p15
629.5M 10.4M 619.1M 2% /cache
/dev/block/mmcblk0p20
25.5G 1.7G 22.5G 7% /data
/dev/block/mmcblk0p13
2.0G 32.0M 1.9G 2% /system
~ #

3.) cat /cache/system-image-upgrader.log
~ # cat /cache/system-image-upgrader.log
Starting image Upgrade pre
Processing the command file
Done upgrading: Sun Jan 4 23:02:13 GMT 1970
tune2fs 1.42.9 (28-Dec-2013)
Setting reserved blocks percentage to 5% (339916 blocks)

4.) cat /cache/recovery/fail_log
There is no fail log. See below what`s there:

/cache # ls -a
. lost+found system-image-upgrader.log
.. recovery test.log

@NeoTheThird: Just to let you know, I`m still working to get you the logs. Even with the original android recovery my system does not see the usb device (therefore the adb shell cannot find the device). But I did not give up yet...
@advocatux Thanks!

@advocatux This seems to be exactly what I am experiencing as well. I tried the fixed recovery image that z3ntu posted there, booting into recovery with this image works on my phone (but no surprise - installing ubuntu using the lineageos recovery image does not work).

@NeoTheThird Yes I am using linux, I will try this.

@NeoTheThird Thank you very much!

@NeoTheThird, Yes it is, just arrived. I think it did but I never actually started it to the end before trying to install ubuntu.

Thank you both of you. I tried the installer, it seems to me that it does the same as the mdt and the cpt. The come out is the same for me, a blue screen and when I continue pushing anyways it stops at file 3, 16% and freezes.
@NeoTheThird Are there any other boot/recovery images I could try?

Hi advocatux,
thanks for answering. The procedure mentioned in your link is quite the same the magic-device-tool performs. The link to the tar.xz resource in the wiki-link is broken.
Has anyone else different boot and recovery images?
Best regards