https://bugs.kde.org/show_bug.cgi?id=455675
--- Comment #3 from Vlad Zahorodnii <vlad.zahorod...@kde.org> --- Alright, this is a Firefox bug after all. Firefox creates two surfaces - one with the drop shadow, and the other with web page contents. It sets opaque regions on both surfaces, it's worth noting that the drop shadow surface has a hollow/transparent part where web page should be. It appears like when resizing firefox, the web page surface can uncover those hollow parts. Since firefox says that the hollow part is opaque, kwin won't try to repaint the area below it and you will see artifacts as in the video. Why did it show up in 5.25? We made kwin use opaque region hints more "aggressively" in order to avoid repainting screen areas that are covered by opaque regions. So if you scroll a web page in firefox and firefox is the top most window, kwin should try to repaint firefox and nothing more. That being said, this is a firefox bug. It should either ensure that web page surface always covers that hollow area (it would be the best solution as it is going to make window resizing more pleasant) or not set an opaque region in the drop shadow surface. I will file a bug report in bugzilla.mozilla.org if it's not already and link it here. -- You are receiving this mail because: You are watching all bug changes.
