Lightning Warp Mouse Button Issue

Have Ball Lightning on LMB/RMB
Have Lightning Warp on LMB/RMB (opposite of whatever one you choose above)
Cast Ball Lightning near an enemy, and then make sure your cursor is over the enemy so their name is highlighted
Press/hold the mouse button that Lightning Warp is assigned to

Expected Behaviour:
Lightning Warp procs on Ball Lightnings

Actual Behaviour:
Nothing happens when Lightning Warp is pressed

This isn't the first skill I've seen that interacts like this either. I've had skills on mouse buttons in the last leagues (maybe even EA release) that were like this and it still hasn't been fixed.