Just upgraded to Fedora 40 and plasma 6 to find out that now the screen isn't black at 0%.
When you think about it, a black screen at 0% is the semantically correct behaviour (zero percent means... well, nothing).
Looking at the code in this MR, I don't see any option that would allow the old behaviour. Or is there?
In my opinion the fix is incomplete because it breaks the current functionality. Some will like it (most, according to the author) but others like me won't because they're relying on it.
Consequently there should be a way to select the level of brightness for 0%. Make it a GUI checkbox or a system flag. This option could select 1% by default, and that's fine.
Maybe there is a more recent MR that allows to get the old behaviour?