Clicking down with mouse problem

Hey, so I recently swapped from using Elvui to the default UI in preparation for the Midnight changes. There is a problem though, I do mouse click some of my non rotational abilities. In default UI the ability activation on key down seems to only apply to literal key presses and not mouse clicks. In Elvui ability activation for key down works on a mouse click. Is It possible in the default UI to have abilities activate on mouse click down? If this is not currently possible in the default UI it absolutely should be added for Midnight. Not having mouse click down work in default UI makes it so when hitting some of those abilities it doesn’t activate them and I have to click them multiple times in order to get them to activate. Thank you to anyone who can give me a solid answer or help me remedy the problem.