Support mouse events clicked on the tab bar but outside of any tab (bug#41343)

* lisp/tab-bar.el (tab-bar--key-to-number): Return non-nil non-numeric t
when no tab is used.  Return nil for current-tab.
(tab-bar-mouse-select-tab, tab-bar-mouse-close-tab): Do nothing
when tab-bar--key-to-number returns non-nil non-numeric t
for click events outside of any tab.
(tab-bar-mouse-context-menu): Add context menu when mouse is clicked
outside of tabs.  Add "Duplicate" alongside with "Close" to the menu
used when mouse is clicked on a tab.
(toggle-tab-bar-mode-from-frame, toggle-frame-tab-bar): Move code
closer to 'tab-bar-show'.

* src/xdisp.c (handle_tab_bar_click): Return Qtab_bar with empty list
when mouse is clicked on the tab bar but outside of any tab.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/xdisp.c b/src/xdisp.c
index 45c7090fc00..d30a68570f0 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -13774,7 +13774,7 @@ handle_tab_bar_click (struct frame *f, int x, int y, bool down_p,
   frame_to_window_pixel_xy (w, &x, &y);
   ts = get_tab_bar_item (f, x, y, &glyph, &hpos, &vpos, &prop_idx, &close_p);
   if (ts == -1)
-    return Qnil;
+    return Fcons (Qtab_bar, Qnil);
 
   /* If item is disabled, do nothing.  */
   enabled_p = AREF (f->tab_bar_items, prop_idx + TAB_BAR_ITEM_ENABLED_P);