When saving frame, include date

load/page.js

@@ -1344,10 +1344,11 @@ function Page(debug) {
 
 		var page = {
 			'version': 2,
-			'attrs': p.attrs,
-			'cost': p.cost,
-			'key': p.key,
-			'content': p.raw,
+			'attrs': this.attrs,
+			'cost': this.cost,
+			'key': this.key,
+			'date': this.__properties__.date,
+			'content': this.raw,
 		};
 
 		var body = LZString.compressToBase64(JSON.stringify(page))+FRAMES_EOF_MARKER;