Putting a fix into /etc/environment to kill the overlay scrollbars worked but there was an objection to allowing the theme to put it there. So we are directing our solution to /etc/X11/Xsession.d/52gtk3-nooverlayscrollbar-nocsd instead. Here's the magic:
# This file is sourced by Xsession(5), not executed.
# This file configures the global behavior of GTK3 "hidden" overlay
# scrollbars and client side decorations. These settings may be overridden
# by individual users by setting the same variables to different values in
# in their ~/.xsessionrc.
BASESTARTUP=${STARTUP%% *}
BASESTARTUP=${BASESTARTUP##*/}
if [ "$BASESTARTUP" = x-session-manager ]; then
BASESTARTUP=$(basename $(readlink /etc/alternatives/x-session-manager))
fi
case "$BASESTARTUP" in
gnome-session*)
# This is GNOME, make sure settings are left at their defaults.
unset GTK_CSD
unset GTK_OVERLAY_SCROLLING
unset LIBOVERLAY_SCROLLBAR
;;
*)
# Not GNOME, and the user didn't specify settings themselves,
# so set them to 0.
if [ -z "$GTK_OVERLAY_SCROLLING" ] ; then
GTK_OVERLAY_SCROLLING=0
fi
export GTK_OVERLAY_SCROLLING
if [ -z "$LIBOVERLAY_SCROLLBAR" ] ; then
LIBOVERLAY_SCROLLBAR=0
fi
export LIBOVERLAY_SCROLLBAR
if [ -z "$GTK_CSD" ] ; then
GTK_CSD=0
fi
export GTK_CSD
;;
esac
And here's the antidote to reverse it:
# To disable the Clearlooks-Phénix-Purpy GTK3 hack
# place the following lines in ~/.xsessionrc:
GTK_OVERLAY_SCROLLING=1
export GTK_OVERLAY_SCROLLING
LIBOVERLAY_SCROLLBAR=1
export LIBOVERLAY_SCROLLBAR
GTK_CSD=1
export GTK_CSD
Putting a fix into /etc/environment to kill the overlay scrollbars worked but there was an objection to allowing the theme to put it there. So we are directing our solution to /etc/X11/Xsession.d/52gtk3-nooverlayscrollbar-nocsd instead. Here's the magic:
And here's the antidote to reverse it: