During cube animation, 1/4 top up corner of the screen is black. I attached a screen recording video: https://img.vim-cn.com/5b/1c99044633df8bf56b8af9631873334828fd7b.ogv Reproducible: Always Steps to Reproduce: 1. Select Cube as Virtual Desktop animation 2. Try switch virtual desktop 3. See black screen Actual Results: 1/4 top up corner of the screen is black Expected Results: Showing cube normally
From the video it looks like there is a window on the top right which is not included in the animation. To confirm you could change the settings to animate all windows (including panels and windows on all desktops).
Wow thank you for the quick answer. Yes, you are right. By animating all windows including panels, the misbehavior is gone. But another question is, what/who owns that (invisible) panel on the top right corner? I tried to close all opening applications, including yakuake and xembedsniproxy, leaving just plasma on the desktop, and the problematic panel is still there. I can reproduce this misbehavior on 3 of my laptops, one of them is a fresh installation of archlinux and kde5. (Now I think this might be a bug outside kwin but on plasma side. Should I close this bug report first?)
run "xwininfo -root -tree" and compare the output to the covered region. If you can spot the offending window, run "xwininfo -id <id of the window>" and "xprop -id <id of the window>" With a little luck, that'll hint the responsible client.
Thanks for the hint. It seems the window is owned by plasmashell, and it is from the panel (even with an empty panel). If I put an empty panel on the top or left side of my screen, the black window will appear. If the empty panel is on the right or bottom side of my screen, the black window is gone.
can you attach xprop and xwininfo of the window?
good detective work! My suggestion is to report a new bug against plasmashell with your findings. For this bug: well everything seems fine from KWin side, so I'm going to mark it accordingly.
I reported to plasmashell: https://bugs.kde.org/show_bug.cgi?id=361516 Thank you for your time by helping me look into this.
Something's odd about it - the shown window is 800x450+800+0, but the one in the props is 640x480+0+0 Also the window from xwininfo is "Map State: IsUnMapped", so it should probably not be painted. Notably since it's also "Override Redirect State: yes" although it has properties that you'd expect for a managed window. Most interesting though is "_XEMBED_INFO(_XEMBED_INFO) = 0x0, 0x1" - smells like xembed-sni-proxy? Try to kill the xembedsniproxy process.
I think I have done `pkill xembedsniproxy` before collecting the output. To make sure, I killed all apps, leaving just konsole and plasmashell and kwin, and get the output again: https://bugs.kde.org/show_bug.cgi?id=361516#c1 Is it possible that xembedsniproxy somehow created a window and left it open under the name of plasma even after xembedsniproxy itself is dead? Is there other suspicious window in the output of the root tree? Should I provide other information?
(In reply to farseerfc from comment #9) > Is it possible that xembedsniproxy somehow created a window and left it open > under the name of plasma even after xembedsniproxy itself is dead? No. The proxy may cause plasma to create a window, but windows go with their X11 clients. > Is there other suspicious window in the output of the root tree? Nope. Actually no window in the list matches the black square and even the 640x480 one should not be painted (it's not mapped) While apparently related to the plasmashell panel, I doubt the black quarter is a real window. Do you have "quick tiling" enabled ("kcmshell5 kwinscreenedges") And if so: does the problem remain if you disable it and restart "kwin_x11 --replace &"?
> Do you have "quick tiling" enabled ("kcmshell5 kwinscreenedges") Yes, I have them enabled (by default). > And if so: does the problem remain if you disable it and restart "kwin_x11 --replace &"? Yes, the problem remains after I disabled both "Maximize windows by drag them to the top of the screen" and "Tile windows by dragging them to the side of the screen" and restarted kwin_x11.
I noticed a more strange behavior today. I have a qtox opened and then exit qtox, now the cube animation showing both qtox and the black corner. I have confirmed that there is no qtox process in the system. See this video https://img.vim-cn.com/15/a7332eb384ad03c2e7cebe6d5b6b47a97e8252.ogv Maybe this is not a plasma bug?
The qtox window looks like falsely kept referenced by some effect. I assume it will vanish on restarting the compositor (SHIFT+Alt+F12 twice)? That'd be unrelated.
Yes you are right. Restarting the compositor indeed removed qtox's window. It's a different issue.
reproducible?
I ran into this same issue. Exact same thing occurs if I move KDE panel to top of screen. If I move panel back to bottom, the black box goes away. It is panel placement related.
Repeatable if panel is placed on top or left of screen. Goes away if placed on right or bottom. Weird.