Add focus_follows_drop option to focus window on drop done

kitty/boss.py

@@ -1998,6 +1998,8 @@ def on_drop(self, os_window_id: int, drop: dict[str, bytes] | int, from_self: bo
                     if window.is_visible_in_layout:
                         g = window.geometry
                         if g.left <= x < g.right and g.top <= y < g.bottom:
+                            if get_options().focus_follows_drop and window is not tab.active_window:
+                                tab.set_active_window(window)
                             window.on_drop(drop)
                             break
         elif tab_bar.left <= x < tab_bar.right and tab_bar.top <= y < tab_bar.bottom:

kitty/options/definition.py

@@ -866,6 +866,15 @@
 '''
     )
 
+opt('focus_follows_drop', 'no',
+    option_type='to_bool',
+    long_text='''
+When something is dropped onto a window, automatically focus that window. If
+disabled (the default), the drop content is delivered to the target window but
+keyboard focus remains on the previously active window.
+'''
+    )
+
 opt('pointer_shape_when_grabbed', 'arrow',
     choices=pointer_shape_names, ctype='pointer_shape',
     long_text='''