Version: (using Devel) Installed from: Compiled sources OS: Linux It is a small bug but can be annoying because sometimes the taskbar item sticks at the top rather than just flashing. To reproduce, open an application (ie. kcalc) then close the window. Look at the top of the screen directly above the taskbar item and you will see the item flash at the top as it closes. By taskbar item I mean a complete item from the taskbar including the icon, text and the rounded edges/border for a particular application.
Top of the screen? Where is your panel (I assume the taskbar is on a panel)? Is it at the top of the screen or the bottom?
I've seen this as well (using trunk). My panel is at the bottom and occasionally when I open/close a program the task item appears at the top center of the screen for a small fraction of a second. It's manifests in the most obvious way when i'm doing a screenshot (using Ksnapshot from kde3). The screen capture that's taken when the app starts up will sometimes capture during that fraction of a second when the KSnapshot task item that pops at the top of the screen. It'll be right there in the screenshot. It's a pretty minor irritant for me... but just to confirm that I've seen it as well.
My panel is at the bottom of the screen too. Sometimes it stays there and does not disappear unless I drop a new widget onto the desktop. Even though it is a minor annoyance, I think that attention to detail really shines through. Vista took a big hit in credibility for me simply because the titlebars flash when you log out. It is small but it adds up. Apple on the other hand seem to look at all the little details and you can really tell, everything fades or slides without exception and it impresses on a subconscious level. KDE4 still has a lot of telltale annoyances (I think I would take fine polishing over new features anyday), I have faith that they can all be resolved though :)
Same here using trunk Panel is at the bottem. Same opinion as Andrew, though, pretty minor irritant but it is happening.
*** Bug has been marked as fixed ***.