diff --git a/dlls/riched20/editor.c b/dlls/riched20/editor.c
index 3dc11337d88..2ae4f94c623 100644
--- a/dlls/riched20/editor.c
+++ b/dlls/riched20/editor.c
@@ -2646,6 +2646,7 @@ ME_TextEditor *ME_MakeEditor(ITextHost *texthost, BOOL bEmulateVersion10)
 
   ed->hWnd = NULL;
   ed->hwndParent = NULL;
+  ed->sizeWindow.cx = ed->sizeWindow.cy = 0;
   ed->texthost = texthost;
   ed->bEmulateVersion10 = bEmulateVersion10;
   ed->styleFlags = 0;