It may be, that the command fastboot boot is not supported on FP5. In this case it can be possible to use fastboot flash instead. But i can not guarantee that it will work. Be ready to reflash if things goes wrong.
I downloaded the package from Fairphone (FP6.QREL.15.91.0), extracted the boot,img, copied it to the FP6, patched the file with magisk and copied it back to my computer. (developer options activated, device unlocked(_critical), adb active:
doing it by fastboot flash boot (or boot_a or boot_b) magisk_patched_boot.img
and fastboot reboot afterwards gives no success: device boots, but in magisk app ist just says
installed: not available
zygisk: no
ramdisk: yes
so I am not able to patch the device (which shouldn’t be necessary when flashing a patched boot.img) - there is still no root.
Today I tried something new:
I took the complete installation-package, extracted it, replaced the original boot.img with my magisk_patched_boot.img, corrected the sha256sum for the boot.img and made a complete factory reset as fairphone describes. Everything successful, but still no root-access.
Has anyone an idea, what goes wrong?
Is there a problem with magisk as root-tool?
Do I forget something else to do?
I mean I did the exact same thing, just with apatch instead of magisk. If I patch it with apatch and flash it, root works for me. Should be the same for everyone.
But I haven’t tried magisk