Fix deleting windows that are not the last window via remote control leaving no window focused

Fixes #3619

docs/changelog.rst

@@ -50,6 +50,9 @@ To update |kitty|, :doc:`follow the instructions <binary>`.
 - Fix passing STDIN to launched background processes causing them to not inherit
   environment variables (:pull:`3603`)
 
+- Fix deleting windows that are not the last window via remote control leaving
+  no window focused (:iss:`3619`)
+
 
 0.20.3 [2021-05-06]
 ----------------------

kitty/window_list.py

@@ -330,6 +330,8 @@ class WindowList:
                 if self.groups:
                     if self.active_group_idx == i:
                         self.make_previous_group_active(notify=False)
+                    elif self.active_group_idx >= len(self.groups):
+                        self._active_group_idx -= 1
                 else:
                     self._active_group_idx = -1
                 break