Oops I did it again...BIOS/UEFI problem?

yes. that is how i understood ‘testing’ as well in the Debian family context.

once you get near the end of the testing cycle (it’s usually marked in the release version number as a higher number and by looking at earlier testing release cycles you can deduce what the final-ish version is going to be and WHEN it’s going to happen ~ ) the ‘testing’ is near enough to be considered ‘stable’ and if you don’t update/upgrade daily you should be able to avoid the small ‘typos’ etc. that even devs. sometimes make (i.e not all updates are necessarily of critical importance especially in the ‘testing’ cycle)

correct me if i’m wrong please.