https://bugs.kde.org/show_bug.cgi?id=522135
--- Comment #3 from Pavel Dobiáš <[email protected]> --- One more important observation, from my testing I highly suspect the bug is related to calculations of window geometry with fractional scaling when doing the XWayland compatibility. It's not just about clicking, but hover effects and all other operations relating to the mouse cursor's position. Additionally, certain display arrangements (moving the horizontal monitor by a few pixels) don't produce this issue, making it even more obscure, but most importantly revealing an important detail. If I understand correctly, XWayland with multiple screens works by basically creating a huge shared space, where Kwin manages the XWayland clients to behave in the same way as the Wayland native clients. This means that during the calculation of the window geometry, there are very likely rounding issues caused by the combination of fractional scaling and the conversion to X server coordinates. Also it seems that odd numbers are more likely to have this problem, further suggesting this being the case. Note that I don't understand kwin's codebase at all, so I can't make well informed judgement on this and I only go off of the surface level observations and knowledge I have about the system, but I'm fairly certain it's a simple rounding error in the geometry conversion between the internal kwin's wayland native system and the xwayland compatibility server. -- You are receiving this mail because: You are watching all bug changes.
