the only way I can see what you're describing happen is if the 2nd button click is only registering right next to the right edge of the screen, hiding the explosion behind the status bar.
the game logic clearly detects your press if the on-screen grenades decrease, and the only area of the screen you get the behaviour you mention is if you launch one where you can't see it.
I've never heard of the bug before, so it's more likely a user / setup error than anything else.