diff --git a/dom/apps/src/Webapps.js b/dom/apps/src/Webapps.js
index 939a0db982d8..47a3156159f0 100644
--- a/dom/apps/src/Webapps.js
+++ b/dom/apps/src/Webapps.js
@@ -884,7 +884,7 @@ WebappsApplicationMgmt.prototype = {
         }
         break;
       case "Webapps:Uninstall:Return:OK":
-        Services.DOMRequest.fireSuccess(req, msg.origin);
+        Services.DOMRequest.fireSuccess(req, msg.manifestURL);
         break;
       case "Webapps:Uninstall:Return:KO":
         Services.DOMRequest.fireError(req, "NOT_INSTALLED");
diff --git a/dom/apps/src/Webapps.jsm b/dom/apps/src/Webapps.jsm
index a242eba6466a..2e6c76feba37 100755
--- a/dom/apps/src/Webapps.jsm
+++ b/dom/apps/src/Webapps.jsm
@@ -2080,14 +2080,11 @@ this.DOMApplicationRegistry = {
         return false;
       }
 
-      // Disallow multiple hosted apps installations from the same origin for now.
-      // We will remove this code after multiple apps per origin are supported (bug 778277).
-      // This will also disallow reinstalls from the same origin for now.
+      // Disallow reinstalls from the same manifest url for now.
       for (let id in this.webapps) {
-        if (this.webapps[id].origin == app.origin &&
-            !this.webapps[id].packageHash &&
+        if (this.webapps[id].manifestURL == app.manifestURL &&
             this._isLaunchable(this.webapps[id])) {
-          sendError("MULTIPLE_APPS_PER_ORIGIN_FORBIDDEN");
+          sendError("REINSTALL_FORBIDDEN");
           return false;
         }
       }