On old forum posts I found multiple people running into this problem, but I wonder if people actually succeeded (having the right security patch) in locking their bootloader, as the tutorial also bluntly says " If you installed a 3rd-party OS, locking your bootloader might prevent your device from booting correctly."
Is the different android version (11 vs 12) a problem for locking it? Did anyone manage to lock their Fairphone bootloader after installing /e/OS?
Yes, in the past I’ve successfully locked the bootloader after installing /e/OS and I’ve also ready several reports about the same success.
But as you’ve mentioned above it will probably not work as long as the security patch level (date) is older for /e/OS (so in your described case I’d expect it to fail).
You might just try it out anyway as long as OEM unlocking is enabled, (you should be safe then). But it’s still on your own risk…
Thanks! Good to know it can work. I did try it and ./fastboot flashing lock_critical worked but ./fastboot flashing lock threw a warning that something was corrupted and left me trapped in fastboot. I managed to get it back working by unlocking it again. I think I’ll wait for the security patch and then try again.
Thanks for trying it out (you’re indeed courageous ) and sharing the result here!
Actually this is all what I’d expected (also that lock_critical did not yet create any problem).
Just be aware (actually I’m quite sure you are already) that your next attempt (after new security patch is here) will again imply a factory reset…