diff --git a/src/testdir/test_popupwin.vim b/src/testdir/test_popupwin.vim
index 06a33d4..d100dc9 100644
--- a/src/testdir/test_popupwin.vim
+++ b/src/testdir/test_popupwin.vim
@@ -272,12 +272,17 @@
 func Test_popup_in_tab()
   " default popup is local to tab, not visible when in other tab
   let winid = popup_create("text", {})
+  let bufnr = winbufnr(winid)
   call assert_equal(1, popup_getpos(winid).visible)
   tabnew
   call assert_equal(0, popup_getpos(winid).visible)
   quit
   call assert_equal(1, popup_getpos(winid).visible)
+
+  call assert_equal(1, bufexists(bufnr))
   call popup_clear()
+  " buffer is gone now
+  call assert_equal(0, bufexists(bufnr))
 
   " global popup is visible in any tab
   let winid = popup_create("text", {'tab': -1})
diff --git a/src/version.c b/src/version.c
index 8f3d086..28877cb 100644
--- a/src/version.c
+++ b/src/version.c
@@ -778,6 +778,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1521,
+/**/
     1520,
 /**/
     1519,
diff --git a/src/window.c b/src/window.c
index d293bad..c15a861 100644
--- a/src/window.c
+++ b/src/window.c
@@ -2324,12 +2324,13 @@
 }
 
 /*
- * Close the buffer of "win" and unload it if "free_buf" is TRUE.
+ * Close the buffer of "win" and unload it if "action" is DOBUF_UNLOAD.
+ * "action" can also be zero (do nothing) or DOBUF_WIPE.
  * "abort_if_last" is passed to close_buffer(): abort closing if all other
  * windows are closed.
  */
     static void
-win_close_buffer(win_T *win, int free_buf, int abort_if_last)
+win_close_buffer(win_T *win, int action, int abort_if_last)
 {
 #ifdef FEAT_SYN_HL
     // Free independent synblock before the buffer is freed.
@@ -2350,8 +2351,7 @@
 
 	set_bufref(&bufref, curbuf);
 	win->w_closing = TRUE;
-	close_buffer(win, win->w_buffer, free_buf ? DOBUF_UNLOAD : 0,
-								abort_if_last);
+	close_buffer(win, win->w_buffer, action, abort_if_last);
 	if (win_valid_any_tab(win))
 	    win->w_closing = FALSE;
 	// Make sure curbuf is valid. It can become invalid if 'bufhidden' is
@@ -2462,7 +2462,7 @@
 	out_flush();
 #endif
 
-    win_close_buffer(win, free_buf, TRUE);
+    win_close_buffer(win, free_buf ? DOBUF_UNLOAD : 0, TRUE);
 
     if (only_one_window() && win_valid(win) && win->w_buffer == NULL
 	    && (last_window() || curtab != prev_curtab
@@ -4894,7 +4894,7 @@
     void
 win_free_popup(win_T *win)
 {
-    win_close_buffer(win, TRUE, FALSE);
+    win_close_buffer(win, DOBUF_WIPE, FALSE);
 # if defined(FEAT_TIMERS)
     if (win->w_popup_timer != NULL)
 	stop_timer(win->w_popup_timer);