diff --git a/src/popupwin.c b/src/popupwin.c
index 436238f..47e7338 100644
--- a/src/popupwin.c
+++ b/src/popupwin.c
@@ -1941,7 +1941,7 @@
 	buf->b_p_ul = -1;	// no undo
 	buf->b_p_swf = FALSE;   // no swap file
 	buf->b_p_bl = FALSE;    // unlisted buffer
-	buf->b_locked = TRUE;
+	buf->b_locked = TRUE;	// prevent deleting the buffer
 
 	// Avoid that 'buftype' is reset when this buffer is entered.
 	buf->b_p_initialized = TRUE;