Bug 1105857 - [Messages] User doesn't receive any notification about incoming message if native modal dialog is shown. r=schung

Sure to rtl changes.
Messurements are: 1.5rem  on the sides (included in the menu) and distance between buttons 1rem.
You could also do: 0.5 on each side of the buttons and then change the menu to have pading left and right 1 rem. Whatever you preffer :)