SUMMARY *** There is a drag handle button to select a custom area of the screen to map it to the tablet. This button is a bit hard to use by tablet as well as mouse. If it is dragged vertically it scrolls the entire kcm page STEPS TO REPRODUCE 1. Go to tablet configuration page in systemsettings under wayland 2. choose custom area in the options and click and drag the drag handle button. OBSERVED RESULT Whole kcm screen scrolls up EXPECTED RESULT A selection outline drag should be initiated.
Yeah it seems like you have to drag left or right first, and then you can drag it up or down. If you drag down immediately, it triggers scrolling code that shouldn't be triggered. Might be an issue in Kirigami, but needs investigation here first.
This was fixed by the fix for Bug 460376 in Plasma 5.26.3. *** This bug has been marked as a duplicate of bug 460376 ***