Do not restore history flag if it was never set.

2 files changed, 4 insertions, 1 deletions

diff --git a/screen.c b/screen.c
index c3e5da70..898cc860 100644
--- a/screen.c
+++ b/screen.c
@@ -536,6 +536,7 @@ screen_alternate_on(struct screen *s, struct grid_cell *gc, int cursor)
 
 	grid_view_clear(s->grid, 0, 0, sx, sy, 8);
 
+	s->saved_flags = s->grid->flags;
 	s->grid->flags &= ~GRID_HISTORY;
 }
 
@@ -579,7 +580,8 @@ screen_alternate_off(struct screen *s, struct grid_cell *gc, int cursor)
 	 * Turn history back on (so resize can use it) and then resize back to
 	 * the current size.
 	 */
-	s->grid->flags |= GRID_HISTORY;
+	if (s->saved_flags & GRID_HISTORY)
+		s->grid->flags |= GRID_HISTORY;
 	if (sy > s->saved_grid->sy || sx != s->saved_grid->sx)
 		screen_resize(s, sx, sy, 1);
 
diff --git a/tmux.h b/tmux.h
index 3cc46df1..fbf10cf4 100644
--- a/tmux.h
+++ b/tmux.h
@@ -761,6 +761,7 @@ struct screen {
 	u_int			 saved_cy;
 	struct grid		*saved_grid;
 	struct grid_cell	 saved_cell;
+	int			 saved_flags;
 
 	bitstr_t		*tabs;
 	struct screen_sel	*sel;