Kelvin and Ivy bomb not working after changing buttons

[Sanosen]

In sandbox mode:
On ivy.
- I changed the bomb skill to mouse 4
- press mouse 4 to get the indicator
- pressing left click doesn't throw the bomb anymore
- Change bomb skill back to 1
- press 1 to get the indicator
- pressing left click doesn't throw the bomb

Change to Kelvin, exact same problem.

Ivy's and Kelvin's other skills work just fine.
Left click to shoot weapon works just fine.
(alt was bound to self cast, help was unbound completely, i use tab instead)

Rebooted the game problem was still present.
Resetting hotkeys (button in menu) fixed the problem. Couldn't reproduce by changing hotkeys the same after.