7fabf0d896
When creating popover with `UI_popover_begin` the popover block is created just once without a region and since `UI_popover_begin` blocks are not support refreshing, layout panels may not be compatible in this kind of popover since open/close state cannot be refreshed either. Only `UILayout.popover(...)` popovers are supported to have layout panels. Pull Request: https://projects.blender.org/blender/blender/pulls/119796