When a plasma panel pops up from hidden state, kwin treats it as normal window and apply window placing rules to it. It seems this only happens to the extra panel I put on top of the screen, the main panel on the bottom somehow behave normally. When I set the placing policy to "center". The panel will always popup in the middle of the screen. Usually I use the "smart" policy, then whenever some window is on the top of the screen, the panel will be move to somewhere to avoid the overlapping. I believe this is part of the reason of BUG:273618. Reproducible: Always Steps to Reproduce: 1. Add an panel on top and have it hide itself automatically 2. Change the placing policy to center 3. Move the mouse around the trigger the top panel to show itself Actual Results: The panel shows up in the middle of the screen Expected Results: The panel shows up on the top
in konsole, run sleep 10; xprop | _NET_WM_WINDOW_TYPE trigger the panel before the sleep times out and post the output. I *had* this behavior (autohiding panel is randomly placed) A LOT, but after wiping plasmarc it was gone. Unfortunately i never had the idea to check whether the panel tags itself as normal window (just assumed it failed on geometry calculation)
I assume you mean "sleep 10; xprop | grep _NET_WM_WINDOW_TYPE", the output is like this: _NET_WM_WINDOW_TYPE(ATOM) = _NET_WM_WINDOW_TYPE_DOCK I just deleted plasmarc the behavior is still the same.
Surprisingly (?) KWin does not skip placing docks in general but relies on them to set a position with their map request (ie have called QWidget::setGeometry()) Wild guess: could it be that the geometry is set before the window is set to be ARGB or is the panel altered otherwise or is the geometry set after the dock is shown?
The bug is reported against KWin 4 and also against behavior of plasma 4. If this is still an issue with Plasma 5's panels, please report a new bug.