Fix padding color not tracking active window bg color

kitty/boss.py

@@ -320,6 +320,15 @@ class Boss:
         self.current_key_press_info = key, scancode, action, mods
         return self.dispatch_action(key_action)
 
+    def default_bg_changed_for(self, window_id):
+        w = self.window_id_map.get(window_id)
+        if w is not None:
+            tm = self.os_window_map.get(w.os_window_id)
+            if tm is not None:
+                t = tm.tab_for_id(w.tab_id)
+                if t is not None:
+                    t.relayout_borders()
+
     def dispatch_action(self, key_action):
         if key_action is not None:
             f = getattr(self, key_action.func, None)

kitty/tabs.py

@@ -426,6 +426,11 @@ class TabManager:  # {{{
         if t is not None:
             return t.active_window
 
+    def tab_for_id(self, tab_id):
+        for t in self.tabs:
+            if t.id == tab_id:
+                return t
+
     def move_tab(self, delta=1):
         if len(self.tabs) > 1:
             idx = self.active_tab_idx

kitty/window.py

@@ -228,7 +228,7 @@ class Window:
         pass  # TODO: Implement this
 
     def change_colors(self, changes):
-        dirtied = False
+        dirtied = default_bg_changed = False
 
         def item(raw):
             if raw is None:
@@ -242,8 +242,12 @@ class Window:
                 continue
             dirtied = True
             setattr(self.screen.color_profile, which.name, val)
+            if which.name == 'default_bg':
+                default_bg_changed = True
         if dirtied:
             self.screen.mark_as_dirty()
+        if default_bg_changed:
+            get_boss().default_bg_changed_for(self.id)
 
     def report_color(self, code, r, g, b):
         r |= r << 8