diff --git a/src/sbbs3/js_uifc.c b/src/sbbs3/js_uifc.c
index e34989813068e0f7d3dc9d051583ffe6d9c309b6..423b8eb319f791bdd935029a4ecdea34796934c9 100644
--- a/src/sbbs3/js_uifc.c
+++ b/src/sbbs3/js_uifc.c
@@ -369,6 +369,8 @@ static JSBool js_showbuf_ctx_constructor(JSContext *cx, uintN argc, jsval *argli
 		JS_ReportError(cx, "calloc failed");
 		return JS_FALSE;
 	}
+	p->height = INT_MAX;
+	p->width = INT_MAX;
 	if(!JS_SetPrivate(cx, obj, p)) {
 		JS_ReportError(cx, "JS_SetPrivate failed");
 		return JS_FALSE;