diff --git a/src/ecmascript/spidermonkey/window.cpp b/src/ecmascript/spidermonkey/window.cpp
index 6a0892c67..a5f2e74c4 100644
--- a/src/ecmascript/spidermonkey/window.cpp
+++ b/src/ecmascript/spidermonkey/window.cpp
@@ -57,6 +57,8 @@
 
 static bool window_get_property_closed(JSContext *cx, unsigned int argc, JS::Value *vp);
 static bool window_get_property_event(JSContext *cx, unsigned int argc, JS::Value *vp);
+static bool window_get_property_innerHeight(JSContext *cx, unsigned int argc, JS::Value *vp);
+static bool window_get_property_innerWidth(JSContext *cx, unsigned int argc, JS::Value *vp);
 static bool window_get_property_location(JSContext *cx, unsigned int argc, JS::Value *vp);
 static bool window_set_property_location(JSContext *cx, unsigned int argc, JS::Value *vp);
 static bool window_get_property_parent(JSContext *ctx, unsigned int argc, JS::Value *vp);
@@ -132,6 +134,8 @@ JSClass window_class = {
 JSPropertySpec window_props[] = {
 	JS_PSG("closed",	window_get_property_closed, JSPROP_ENUMERATE),
 	JS_PSG("event",		window_get_property_event, JSPROP_ENUMERATE),
+	JS_PSG("innerHeight",	window_get_property_innerHeight, JSPROP_ENUMERATE),
+	JS_PSG("innerWidth",	window_get_property_innerWidth, JSPROP_ENUMERATE),
 	JS_PSGS("location",	window_get_property_location, window_set_property_location, JSPROP_ENUMERATE),
 	JS_PSG("parent",	window_get_property_parent, JSPROP_ENUMERATE),
 	JS_PSG("self",	window_get_property_self, JSPROP_ENUMERATE),
@@ -809,6 +813,122 @@ window_get_property_event(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	return true;
 }
 
+static bool
+window_get_property_innerHeight(JSContext *ctx, unsigned int argc, JS::Value *vp)
+{
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
+#endif
+	JS::CallArgs args = CallArgsFromVp(argc, vp);
+	JS::RootedObject hobj(ctx, &args.thisv().toObject());
+
+	struct view_state *vs;
+	JS::Realm *comp = js::GetContextRealm(ctx);
+
+	if (!comp) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	struct ecmascript_interpreter *interpreter = (struct ecmascript_interpreter *)JS::GetRealmPrivate(comp);
+
+	/* This can be called if @obj if not itself an instance of the
+	 * appropriate class but has one in its prototype chain.  Fail
+	 * such calls.  */
+	if (!JS_InstanceOf(ctx, hobj, &window_class, NULL)) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	vs = interpreter->vs;
+
+	if (!vs) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	struct document_view *doc_view = vs->doc_view;
+
+	if (!doc_view) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	struct session *ses = doc_view->session;
+
+	if (!ses) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	args.rval().setInt32(doc_view->box.height * ses->tab->term->cell_height);
+
+	return true;
+}
+
+static bool
+window_get_property_innerWidth(JSContext *ctx, unsigned int argc, JS::Value *vp)
+{
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
+#endif
+	JS::CallArgs args = CallArgsFromVp(argc, vp);
+	JS::RootedObject hobj(ctx, &args.thisv().toObject());
+
+	struct view_state *vs;
+	JS::Realm *comp = js::GetContextRealm(ctx);
+
+	if (!comp) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	struct ecmascript_interpreter *interpreter = (struct ecmascript_interpreter *)JS::GetRealmPrivate(comp);
+
+	/* This can be called if @obj if not itself an instance of the
+	 * appropriate class but has one in its prototype chain.  Fail
+	 * such calls.  */
+	if (!JS_InstanceOf(ctx, hobj, &window_class, NULL)) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	vs = interpreter->vs;
+
+	if (!vs) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	struct document_view *doc_view = vs->doc_view;
+
+	if (!doc_view) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	struct session *ses = doc_view->session;
+
+	if (!ses) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	args.rval().setInt32(doc_view->box.width * ses->tab->term->cell_width);
+
+	return true;
+}
+
 static bool
 window_get_property_location(JSContext *ctx, unsigned int argc, JS::Value *vp)
 {