The synthesized double-tap that hides a zone's tab strip rode every tab's
pointerdown (generic pane drag and each pane's tabDrag), so a routine
double-click on a tab (select a title, retry a click) vanished the whole
bar and stranded the zone with no tab, no close X, and no way back but a
right-click. Keep the documented hide gesture on the strip background
only, and add its inverse as recovery: double-tap a hidden zone's body
restores the strip. Regression tests pin both sides of the grammar.
abundantbeing
3aeb592863