diff --git a/src/window.c b/src/window.c
index 7d78b5f..7322905 100644
--- a/src/window.c
+++ b/src/window.c
@@ -2475,6 +2475,7 @@
     wp->w_topfill = 0;
 #endif
     wp->w_botline = 2;
+    wp->w_valid = 0;
 #if defined(FEAT_SYN_HL) || defined(FEAT_SPELL)
     wp->w_s = &wp->w_buffer->b_s;
 #endif