It is very easy to misclick. If I want to cancel something, on windows I can just press the other mouse button and cancel the mouse event. In Kubuntu 18.04 we are noticing that it is very easy to right-click and then accidentally click on a menu item on the menu without even noticing that the item was selected. This would be solved by triggering the monu open on mouse-up. This would make it consistent with other systems that had usability studies and presents expected behavior.. KDE currently does not exhibit expected behavior, and it is actually dangerous because unintended input is caused.
about 2 out of 5 times people who click while the mouse is moving didn't mean to do the click. For users with mobility problems, it is extra important to make sure that they actually mean to do the click.. so they may struggle a bit to actually trigger the event, but doing the false event is much worse... better to make them give confirmed good input than start opening a program that will take 10 minutes to load... Also note, the people with mobility problems also often don't have enough money to buy a good computer.
I'm sorry but this is outside the scope and possibilities of a window manager.
Needs to be fixed in Qt, see https://bugreports.qt.io/browse/QTBUG-57849
*** Bug 393695 has been marked as a duplicate of this bug. ***
(In reply to Christoph Feck from comment #4) > *** Bug 393695 has been marked as a duplicate of this bug. *** Thank you!