Okay so, i have a Fairphone 3 with Android10 and I have the three buttons option in the lower bar. I was trying other launchers and i found ones (Nova launcher and Lawnchair) i liked better than the default one (Quickstep). So via USB debugging and ADB i uninstalled Quickstep.
After I did that, the “Recent apps” button (the one on the right, in the lower bar with Back and Home) has stopped working.
I tried to have a look in settings but it seems I can’t change a thing about the lower bar. Also in the launchers’ settings it seems I can’t change anything. I also tried to relaunch my phone and wipe cache but nothing worked.
I did it also. Same effect.
Also that my FP4 stayed black and ended up in factory reset automatically.
You have to leave it on system. Ignore it and use the other launcher.
You have to install it again.