The right-click ContextMenu's hover listener was a no-op: it never
tracked the hovered row and never rendered a submenu popup, so every
menu item with a submenu (Proxy, Cache, Color, Show Thumbnails, Zoom,
Playback Resolution...) was a dead end. Hover now drives the row
highlight and opens the parent's submenu anchored to its right (the
menu bar's model), with keyboard Left/Right to close/open it and Enter
expanding a parent row instead of firing it.
Mike-Solar
e521a8af83