I did not want to be offensive. The meaning of my words was supposed to be literal not ironic. I am sorry if my sentence has been misunderstood.
I am a developer myself, Debian guest maintainer of many packages, I know how bad can be a bug sometimes.
It is for sure a problem in the LCD driver. It is a pity because armbian+new kernel used to work like a charm before the kernel update. Maybe it is possible to rollback to the latest working kernel (not to the legacy 5.4xx).IMO this would help to find the change in the kernel which caused the misbehavior.