This is a regression but I have not identified the release breaking it. It is pretty recent though, and currently happening on 5.9.4. The problem is, in a typical setup with a panel bar at the bottom and a launcher button at the bottom left, the bottom-left most pixel is not clickable. This is pretty annoying as you cannot just "throw" your cursor in the corner and click to open the menu. You have to offset just one pixel top or right for the click to operate.
ame thing happens for closing maximized windows (you can't just throw your cursor to the upper right corner and click).
Cannot reproduce. Does this happen with a freshly created user account?
I found a way to reproduce the "non-reactive bottom-left menu pixel" issue. You just have to NOT use kwin. I could reproduce it with openbox and xfwm4 (not tested any others). Something I also noticed is that when using an "alternative" WM, when resizing the panel height, it will not stay glued to the bottom of the screen. Uploading a screenshot demonstrating this. With kwin it resizes correctly. Something must have changed in the panel behaviour, as I have been using xfwm4 for quite some time before this issue started occuring. The panel also sometimes crashed when being resized with those WM. I have not acquired a backtrace yet.
Created attachment 105274 [details] Panel after a resize on xfwm This looks corrupted, as if the render was truncated.
I discovered it also happens with kwin *IF* compositing is turned off. The only setup not showing this issue for me is kwin with compositing enabled. As soon as kwin compositing is disabled or with openbox or xfwm the panel renders incorrectly (truncated, not flush to the bottom of the screen) which I think is the root cause of the initial bug report. I am using : Xorg 1.19.3 (with modesetting DDX, over mesa 17.0.5 on radeonsi/amdgpu) Plasma 5.9.5 now Applications 17.04.0 Frameworks 5.33.0
This got fixed in plasma 5.10. Closing.