Bug 504212

SUMMARY

Complex acceleration-based algorithm that prevents on-hover app category opening in Kickoff (if cursor acceleration and/or speed is high enough) (deployed circa plasma 6.2 release AFAIR) should be removed.

RATIONALE

The feeling of crisp, instant, on-hover app category opening (turned on by default) was really good and it was one of the selling points of release. In a world of sluggish UIs it was a breath of fresh air. But there was one issue - Windows-like default panel/Kickoff layout + left-side placement of categories list made it uncomfortable to launch application from favorite-apps/other lists on the right of categories-list, because users unintentionally opened random app categories by hovering  (app categories are on the way of cursor from bottom left corner to the center of the Kickoff). To make life of the most users (who use default Kickoff settings) easier - the above mentioned acceleration-based algorithm was introduced. Unfortunately It sacrifices crisp, instant, on-hover app category opening if cursor speed is not hellishly slow. This measure was not deemed sufficient and some time later default app category opening mode was switched to Open-on-click.

Open-on-click is the default mode instead of open-on-hover for app categories in Kickoff for a long time. 
This makes above-mentioned complex acceleration-based algorithm no longer needed for its intended purpose (prevent unintentional on-hower app-category opening).

The removal of acceleration-based algorithm will return the feeling of crisp, instant, on-hover app category opening, especially when user quickly switches categories to find needed app inside it (if open-on-hower is activated of course). 

Power-users who use open-on-hower can use it with left-side categories list, which brings back above mentioned unintentional-category-opening problem. There are 3 things to say:
1. Flexible configuration options make existence of suboptimal configs unavoidable all over the Plasma DE.
2. Power-user should be allowed to non-lethally shoot themselves in the foot because because if you are tailoring UX for yourself it is your responsibility to manage consequences of you actions.
3. Since they are already messing with settings and they can solve this problem by moving categories list to the right (as i've done in my case)


STEPS TO REPRODUCE
1. open Kickoff and check "open categories on hover" flag in Kickoff widget settings
2. quickly move cursor on top of app categories list from top to bottom at various speed.
3. observe

OBSERVED RESULT
When cursor comes by another category it usually (but not always!) don't open it

EXPECTED RESULT
As soon as cursor hover over another category this category is opened

SOFTWARE/OS VERSIONS
Operating System: KDE neon 6.3
KDE Plasma Version: 6.3.5
KDE Frameworks Version: 6.14.0
Qt Version: 6.9.0
Kernel Version: 6.11.0-25-generic (64-bit)
Graphics Platform: Wayland
Processors: 28 × Intel® Xeon® CPU E5-2690 v4 @ 2.60GHz
Memory: 62.6 Gib of RAM
Graphics Processor: AMD Radeon RX 550 / 550 Series