How do I properly capture input to avoid browser actions?

Hello,

I've come across an issue in my game, where when you press Shift + Right Click, it opens a context menu from the browser, and ends up locking whatever inputs were being held in the game until the menu is cleared and keys re-pressed. Obviously this is very problematic.

Is there a way to stop this from happening via Construct?

EDIT: After some testing, this appears to be a FireFox specific issue.

Thanks