diff --git a/src/nvim/buffer.c b/src/nvim/buffer.c
index 7afa663fe3..11171617ef 100644
--- a/src/nvim/buffer.c
+++ b/src/nvim/buffer.c
@@ -4425,8 +4425,8 @@ linenr_T buf_delsign(
     }
 
     /* When deleted the last sign needs to redraw the windows to remove the
-     * sign column. */
-    if (buf->b_signlist == NULL) {
+     * sign column. Not when curwin is NULL (this means we're exiting). */
+    if (buf->b_signlist != NULL && curwin != NULL) {
         redraw_buf_later(buf, NOT_VALID);
         changed_cline_bef_curs();
     }
diff --git a/src/nvim/version.c b/src/nvim/version.c
index c93fc5083c..bf0dace6ef 100644
--- a/src/nvim/version.c
+++ b/src/nvim/version.c
@@ -226,7 +226,7 @@ static int included_patches[] = {
   //372,
   371,
   370,
-  //369,
+  369,
   368,
   367,
   //366,
diff --git a/src/nvim/window.c b/src/nvim/window.c
index dccf3e2efc..27fb160035 100644
--- a/src/nvim/window.c
+++ b/src/nvim/window.c
@@ -2001,6 +2001,10 @@ void win_free_all(void)
 
   while (firstwin != NULL)
     (void)win_free_mem(firstwin, &dummy, NULL);
+
+  // No window should be used after this. Set curwin to NULL to crash
+  // instead of using freed memory.
+  curwin = NULL;
 }
 
 #endif