I have a Lenovo G580 laptop with Intel Core i3 2.3 GHz x 4, 4 GB RAM, and Intel Sandybridge graphics controller (integrated). At least on this laptop, there is significant tearing and flickering of various widgets on mouse-out in KDE SC 4.11.2. These include flickering and tearing of tooltips, tearing of the Folder View widget's pop-ups, and flickering of windows during fade-out on close. Reproducible: Always Steps to Reproduce: 1. Configure KWin to use OpenGL rendering (instead of XRender) in Desktop Effects on the hardware mentioned in the description. (May occur on other hardware too.) 2. Enable the Fade effect in Desktop Effects. 3. Open a folder pop-up in the Folder View widget, mouse over into a sub-folder, then mouse out of all the pop-ups. 4. Enable (detailed) tooltips in System Settings and Dolphin, mouse over any icon in these applications, then mouse out. 5. Close any open window larger than about 600x400 pixels. Actual Results: For (3) there is tearing of the pop-ups just after the mouse-out. For (4) there is tearing and flickering of the tooltips on mouse-out. For (5) there is flickering of the window on close. Expected Results: There should be no tearing or flickering in any of the cases. This seems to be a regression because it is not present in KDE SC 4.10.5.
"kcmshell4 kwincompositing", "all effects"" tab, filter for blur, configure the blur effect, disable "save intermediate blur results" -> Problem gone?
(In reply to comment #1) > "kcmshell4 kwincompositing", "all effects"" tab, filter for blur, configure > the blur effect, disable "save intermediate blur results" > > -> Problem gone? Yes. This solution is not obvious to most users. Why is the default setting such that it causes this problem? Is this still a valid bug?
*** This bug has been marked as a duplicate of bug 307112 ***