Full screen kittens: Fix incorrect cursor position after kitten quits

DECOM should be reset only after entering alternate screen as it also
changes cursor position. Fixes #3176

Author: kovidgoyal

docs/changelog.rst

@@ -57,6 +57,9 @@ To update |kitty|, :doc:`follow the instructions <binary>`.
 - Fix a regression in 0.19.0 that caused a rare crash when using the optional
   :opt:`scrollback_pager_history_size` (:iss:`3049`)
 
+- Full screen kittens: Fix incorrect cursor position after kitten quits
+  (:iss:`3176`)
+
 
 0.19.2 [2020-11-13]
 -------------------

kittens/tui/operations.py

@@ -264,7 +264,7 @@ def init_state(alternate_screen: bool = True) -> str:
     ans = (
         S7C1T + SAVE_CURSOR + SAVE_PRIVATE_MODE_VALUES + reset_mode('LNM') +
         reset_mode('IRM') + reset_mode('DECKM') + reset_mode('DECSCNM') +
-        set_mode('DECARM') + reset_mode('DECOM') + set_mode('DECAWM') +
+        set_mode('DECARM') + set_mode('DECAWM') +
         set_mode('DECTCEM') + reset_mode('MOUSE_BUTTON_TRACKING') +
         reset_mode('MOUSE_MOTION_TRACKING') + reset_mode('MOUSE_MOVE_TRACKING') +
         reset_mode('FOCUS_TRACKING') + reset_mode('MOUSE_UTF8_MODE') +
@@ -274,7 +274,7 @@ def init_state(alternate_screen: bool = True) -> str:
         '\033[*x'  # reset DECSACE to default region select
     )
     if alternate_screen:
-        ans += set_mode('ALTERNATE_SCREEN')
+        ans += set_mode('ALTERNATE_SCREEN') + reset_mode('DECOM')
         ans += clear_screen()
     return ans