When closing a program, the task Manager moves program icons on top of each other. This happens when activating a program which is on the bottom of the list, switching to another program which is above it and closing it. The bottom icon moves on top of the icon above it and an empty space is created in the list. This can be reproduced every time. Attached you will find a screenshot of the bug. Reproducible: Always
Created attachment 72283 [details] After closing a window, the Processing icon has moved on top of the Ksnapshot icon, leaving an empty spot above the Firefox icon
I can confirm this, or a very similar bug, exists in KDE 4.9.3 (and many previous versions). The effect is that there can be gaps or overlapping icons in the task manager. However, I can't always reproduce this bugs. Also, sometimes I get a gap but not overlap, and sometimes I get overlap but no gap. I haven't found a pattern. I will be attaching two more screenshots.
Created attachment 75439 [details] See the circled area; the KRDC icon and text is over top of the Okular icon and text. (You may have to zoom in to see it clearly.)
Created attachment 75440 [details] See the circled area; the KRDC icon and text no longer overlap the Okular icon and text. Opening and/or closing pretty much anything will clear up the overlap (making it uncapturable with ksnapshot.)
Created attachment 75450 [details] Overlap of task frames in TaskManager Confirming the issue in 4.9.3, see the attachment
Created attachment 75498 [details] For good measure, here's a screenshot of a gap.
I have the same problem. Sometimes I get gaps, sometimes overlaps, usually both. It tends to happen when I close a window (about 15% of the time), though, and everything goes back to normal once a new window is opened.
I reckon that this is a duplicate of Bug 224447 and (allegedly) will be fixed in 4.11.
*** This bug has been marked as a duplicate of bug 224447 ***