Activities dissapear when you Disable IF-statement

This is crazy…
I did some code in an If-statement. When I disable activitie (Ctrl-D) Everyting!! dissapears…???

I press (Ctrl-D)
Everything disapears??? I can´t use (Ctrl-Z) to go back. Something is very wrong here.

This is a known issue. It will be fixed in the next upcoming patch.