I was working on ~50 pdf documents in okular - this put 50 instances of okular in the task manager and they stacked into one button. To navigate I wanted to right click, get a menu, and select the correct document. If I wasn't quick enough to right click then the preview that is provoked by hovering would kick in and this could freeze the screen for several seconds. Reproducible: Always Steps to Reproduce: Start many instance of an application so they stack in the task manager hover over the task manager button screen <sometimes> freezes generating previews Actual Results: Screen freezes Expected Results: Shouldn't freeze
I am also affected by this bug, when starting ~30 xterms. I can work around the problem by turning off grouping. Using: plasma-desktop 4:5.8.5-0ubuntu1~ubuntu16.04~ppa1
Also seeing this lately.
Since it's in 5.8, it is probably not related to the tooltip redesign in 5.9. I speculate, that it's because of all thumbnails being rendered at the same time. To confirm this, try to minimize most of the 50 windows. Then thumbnail loading should be aborted (as long as not activated in system settings) and there should be no freeze.
Preview loads a little longer than usual - CPU usage increases upon hovering but screen isn't freezing for long periods - tried with ~150 instances of Okular with opened files Plasma: 5.12.2 Apps: 17.12.2 Frameworks: 5.43.0 Qt: 5.10.1 Kernel: 4.14.20-2-MANJARO OS: Netrunner Rolling
Same; let's call this fixed. David, please re-open if you can still see this with KDE Plasma 5.12.2 or later.
Ok - I'm happy with that - thanks!