After somehow forgetting about this, I now note the place to stick the 'patch' override is /usr/share/applications/pidgin.desktop, making the Exec line:
Exec=LIBOVERLAY_SCROLLBAR=0 pidgin
Sadly the whole Unity/Dash morass made it a bit difficult to track that down (and this even for someone well aware of .desktop files, just not sure where the applicable one was sitting).
After somehow forgetting about this, I now note the place to stick the 'patch' override is /usr/share/ applications/ pidgin. desktop, making the Exec line:
Exec=LIBOVERLAY _SCROLLBAR= 0 pidgin
Sadly the whole Unity/Dash morass made it a bit difficult to track that down (and this even for someone well aware of .desktop files, just not sure where the applicable one was sitting).