Created attachment 467318 [details] [diff] [review] patch As bug 587539 shows PaintFrame can be called without a widget, so the assertion at the start of the function fires. This causes some mac reftests with plugins to fail. I added this assertion recently, so I think we should just make it a warning.
How about removing USE_WIDGET_LAYERS in this case to ensure that the rendering still works?
Created attachment 467331 [details] [diff] [review] remove the flag Okay, let's do that.