yep, it’s exactly what I linked in the topic above. a handful of white-over-transparent fills are not working properly in layout. they are transparent png but get exported as opaque white fills.
it seems at the time it flew under the radar and didn’t get a bug report, @colin do you know if it is known (more infos in the other topic, I tested various combos there)
Back then, I created a couple of fills, and they worked ok, only the default ones (only a handful) were bugged