GIMP 2.8.6, single window mode greys out "Maximize" option on right click of window bar, double clicking on title bar does nothing. Gnome 3 shortcut to maximize does nothing... so on and so forth. I haven't touched sessionrc (ever, didn't know it existed until I read this bug report).
Going to Windows and unchecking single window mode fixes the problem, but isn't really what I want...
