Created attachment 102563 [details] A screenshot demonstrating the issue Steps to reproduce: * Have at least 3 windows in a group. * Left-click that group * Right-click a window in that group and select "Close" Expected behavior: * The window closed and disappears from the group, and nothing else happens Actual behavior: * Another window can start showing up in the group -- even windows that are not usually shown, e.g. "plasma". I will attach a screenshot demonstrating this. This is not entirely reproducible because it seems to depend on the exact state of the task manager, i.e. how many groups of which size are presented in which order. Still, it happens frequently for me. Having more windows grouped increases the likelihood of seeing this.
Actually I now frequently get a slightly messed-up task manager even when no windows are grouped. For example, I just used right-click "Close" to close one of two qgit windows I had open (grouping was disabled). Then *both* vanished from the taskbar, and some icons of other windows got swapped. Switching the active window repaired the taskbar, i.e., the missing qgit window came back and the icons all got fixed.
Please attach a screenshot of your Task Manager config dialog.
Created attachment 102657 [details] Screenshot of my task manager settings These are the settings I use most of the time -- even when there are no groups, I occasionally get screwed-up windows in the taskbar. For the original report (closing a window from a group), the settings were the same except that "Grouping" was set to "By Program Name".
The "By Activity" sorting strikes me as the outlier there (it's rarely used).
I don't actually use activities, so this is probably something I changed years ago... However, after disabling this (and enabling the grouping again), I was able to still reproduce the issue on the first try.
*oops* I am sorry I misread what you wrote... I read "setting" instead of "sorting", so I was changing the option "Show only tasks of current activity". Indeed changing the sorting to "Alphabetically" fixes the problem. I have no idea why the sorting option is what it was. I now set it to "By Desktop" and will see how that one behaves. So far, it did not leave things in a bad state; however, the animations when closing a window do look a bit odd -- instead of the closed window being animated to disappear, some other window disappears and then there is a smooth transition if taskbar entires changing their icon and text. That doesn't look right.
Same issue or likely root cause as Bug 369576. *** This bug has been marked as a duplicate of bug 369576 ***