got a ryzon 5 with vega 8, but is a desktop…
my acer got a old amd with ati, got also a boot issue with screen backlight, i can get darker or lighter with it… since for me works is ok , since your laptop is more new then my laptop have to see
Yes, that’s me.
I have used openSUSE Tumbleweed KDE, Ubuntu GNOME and KDE (kubuntu repo), Manjaro KDE (broke after I downloaded deepin from arch), Pop!_OS with gnome.
All worked fine for screen brightness. Even EndeavourOS installer running from usb worked fine
I have tried both acpi_backlight=vendor and video.use_native_backlight=1. None of them worked. I guess I will just have to wait until new Deepin, hope they support newer hardware
Just a shot in the dark…but since you seem to be having success with KDE have you tried using deepin-kwin? If you do you will also need to instal system-settings. You may also want to explore what display manager those other distros are using as opposed to the installed endeavour deepin / the live installer.