Version: (using KDE 4.2.2)
Installed from: Ubuntu Packages
I installed Adobe Air ( 1.5.1) on my 64bit Kubuntu 8.10 KDE 4.2.1 (now on 4.2.2).
Air applications run fine until I minimize them to tray (twhirl, tweetdeck). If I then try to restore it, my Desktop (Kwin) comes unreaktive (seems like Twhirl is restoring from the "systray" then minimizing to it again in and endless, fast loop), can't even switch applications anymore (have then to kill the AIR process from another tty command session)
If I turn compositing (desktop effects) off, everything works as it should.
I started a thread in following forum and another user experienced the same
If this seems to be a KWin issue, reassigning to it.
What is the value of System Settings -> Desktop -> Advanced -> Keep window thumbnails? Does it still occur if set to "never"?
Keep window thumbnails -> never
solves the problem.
What was the original value? If it was "always" then this is a WONTFIX as there is no way to fix it without changes to X.
yes it was "always".
would be good if this goes somewhere into an official documentation.
Not closing yet as more research is needed to see if there is any way KWin can work around the problem.
SVN commit 952987 by lmurray:
State in the GUI that minimization breaks when always keeping taskbar
M +1 -1 main.ui
WebSVN link: http://websvn.kde.org/?view=rev&revision=952987
*** Bug 181848 has been marked as a duplicate of this bug. ***
*** Bug 189292 has been marked as a duplicate of this bug. ***
Always having thumbnails for a window means the window can never be unmapped (in X11 terms). Which is the common way to implement minimizing. I assume the application gets confused by the fact that its attempt to minimize the window don't "work" and gets stuck in a loop. Yet another proof systray sucks and apps should not play with window management. Maybe some ugly hack can be added to KWin to prevent such loop.
*** Bug 184556 has been marked as a duplicate of this bug. ***
I turned on "always" because I use present windows and its pretty awkward otherwise. I have not noticed any problems with minimisation. Is this bug still valid?
Platform Version 4.4.1 (KDE 4.4.1)-kdemod on Arch Linux.
I vote NO. I'm even for reverting this bug. Under KDE 4.5, I actually have a better minimization with Keep Window Thumbnail set to Always. The bug reversion would be like this.
"Keep Window Thumbnail - Always does not break minimizing windows anymore: Please, remove the string suggesting brokenness, since it doesn't applies anymore".
Although I'm testing with KDE 4.5 RC, the KDE 4.4 line already fixed this for me. Please, close this as FIXED and remove the string "brokes minimization" in "Always" setting.
> "Keep Window Thumbnail - Always does not break minimizing windows anymore:
> Please, remove the string suggesting brokenness, since it doesn't applies
This is impossible. It is a technical limitation of the underlying X stack and
this limitation will probably never be fixed. It is possible that you do not
experience the problems, nevertheless it is likely that some apps are broken.
This bug is one of the most annoying bugs, for me...
The bug as described originally is -iff at all- on adobes side (acts on _assumed_ state/ability)
It's however reasonable since usually one can minimize a window on X11.
So the "correct" behavior was to NOT choose the "always" setting (which is not default in vanilla kwin either) - with the effect that "minimized" windows are lost for the compositor (thus the blank/black windows in certain conditions)
To "fix" this one would need a refinement of X11 protocols / the NETWM standard - and that changes would have to be reflected by the clients (in this case adobe air) as well. (so they could as well fix the false assumption which leads to buggy behavior)
The issue would be resolved by alternative display servers (such as wayland) which use offscreen rendering for all clients by design (but of course you'll then as well require a compliant client from adobe for wayland...)
The bug is open because lucas then thought one could have a better solution, but i guess it's rather a "wontfix" - you can still choose whether you prefer true minimization or glitch free effects.
*** Bug 227120 has been marked as a duplicate of this bug. ***
May I ask what does "Keep window thumbnails" do for these three options?
(In reply to comment #18)
> May I ask what does "Keep window thumbnails" do for these three options?
It prevents the window from being actually unmapped when eg. on a different desktop or - in the "always" case, even when minimized in order to provide a "live preview" of the window.
This "bug" is a friction between clients with buggy/optimistic/aggressize iconification implementation and unmapped windows not bein drawables (nor updating) - clients should not go wild if they don't get unmapped for an iconification, but from the compositors POV and on X11 this is a conflict that _cannot_ be resolved. An unmapped client cannot show a live update, so if you want a live preview, you must not unmap the window - if the client cannot deal with that, that's a client problem.
tl;dr - truth is: WONTFIX, sorry.