patch 8.2.0142: possible to enter popup window with CTRL-W p Commit: https://github.com/vim/vim/commit/8bf716cdba0e48f56b8bfcbed0f4c702a705e095 Author: Bram Moolenaar <Bram@vim.org> Date: Thu Jan 23 15:33:54 2020 +0100 patch 8.2.0142: possible to enter popup window with CTRL-W p Problem: Possible to enter popup window with CTRL-W p. (John Devin) Solution: Check entered window is not a popup window. (closes https://github.com/vim/vim/issues/5515)

--- a/src/window.c
+++ b/src/window.c
@@ -4343,8 +4343,15 @@ win_goto(win_T *wp)
     win_T	*owp = curwin;
 #endif
 
+#ifdef FEAT_PROP_POPUP
     if (ERROR_IF_POPUP_WINDOW)
 	return;
+    if (popup_is_popup(wp))
+    {
+	emsg(_("E366: Not allowed to enter a popup window"));
+	return;
+    }
+#endif
     if (text_locked())
     {
 	beep_flush();