scrollbars: don't change border color for insensitive scrollbar buttons
scrollbars: don't change border color for insensitive scrollbar buttons

DoctorJellyface/gnome-themes-standard,cosimoc/gnome-themes-standard,cosimoc/gnome-themes-standard,ChrisCummins/gnome-themes-standard,ChrisCummins/gnome-themes-standard,rgcjonas/adwaita-semidark,Distrotech/gnome-themes-standard,cosimoc/gnome-themes-standard,magcius/gnome-themes-standard,DoctorJellyface/gnome-themes-standard,ChrisCummins/gnome-themes-standard,ChrisCummins/gnome-themes-standard,Distrotech/gnome-themes-standard,rgcjonas/adwaita-semidark,magcius/gnome-themes-standard,cosimoc/gnome-themes-standard,ChrisCummins/gnome-themes-standard,rgcjonas/adwaita-semidark,magcius/gnome-themes-standard,rgcjonas/adwaita-semidark