This is a backport from Mixbus, to leave are 4 "open" pixels at the bottom of the track so one can see the grid-lines between tracks.
This is useful with low region-transparency. grid-lines behind opaque regions are not visible.
f5bc64d00 Add option to leave vertical gap below audio regions
gtk2_ardour/audio_region_view.cc | 8 ++++++++
gtk2_ardour/audio_time_axis.cc | 10 ++++++++++
gtk2_ardour/audio_time_axis.h | 1 +
gtk2_ardour/rc_option_editor.cc | 13 +++++++++++++
gtk2_ardour/ui_config_vars.h | 5 +++++
5 files changed, 37 insertions(+)