I’ve run into the following issue using the click casting feature on my holy paladin:
Having bound spells on my action bar that do not require a target (Aura Mastery, Daybreak, Divine Favor,…) to a mouse button (for example mouse button 4 or mouse button 4 + ctrl etc) those keybinds don’t work anymore when I have a unit frame or target under my cursor. I have to not be hovered over a unit frame to get it to work. I can’t select these spells to setup a click cast binding that matches the keybind of the action bar either, so I need to make a macro of each of these spells to then be allowed to duplicate the keybind in the click cast menu. And only then when I am over a unit frame, I can cast these spells that don’t even need a target to begin with.
It doesn’t make sense that it behaves in this way. With Clique addon this wasn’t an issue. You would still trigger your other mouse button keybinds of targetless spells that aren’t in use with Clique, regardless what unitframe your mouse was over.