diff --git a/browser/components/sessionstore/SessionStorage.jsm b/browser/components/sessionstore/SessionStorage.jsm
index 067a673e679..df3f00ef818 100644
--- a/browser/components/sessionstore/SessionStorage.jsm
+++ b/browser/components/sessionstore/SessionStorage.jsm
@@ -9,6 +9,7 @@ this.EXPORTED_SYMBOLS = ["SessionStorage"];
 const Cu = Components.utils;
 const Ci = Components.interfaces;
 
+Cu.import("resource://gre/modules/BrowserUtils.jsm");
 Cu.import("resource://gre/modules/Services.jsm");
 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
 
@@ -72,9 +73,9 @@ let SessionStorageInternal = {
         return;
       }
 
-      // Get the root domain of the current history entry
-      // and use that as a key for the per-host storage data.
-      let origin = principal.jarPrefix + principal.originNoSuffix;
+      // Get the origin of the current history entry
+      // and use that as a key for the per-principal storage data.
+      let origin = principal.origin;
       if (visitedOrigins.has(origin)) {
         // Don't read a host twice.
         return;
@@ -102,10 +103,9 @@ let SessionStorageInternal = {
    *        {"example.com": {"key": "value", "my_number": 123}}
    */
   restore: function (aDocShell, aStorageData) {
-    for (let host of Object.keys(aStorageData)) {
-      let data = aStorageData[host];
-      let uri = Services.io.newURI(host, null, null);
-      let principal = Services.scriptSecurityManager.getDocShellCodebasePrincipal(uri, aDocShell);
+    for (let origin of Object.keys(aStorageData)) {
+      let data = aStorageData[origin];
+      let principal = BrowserUtils.principalFromOrigin(origin);
       let storageManager = aDocShell.QueryInterface(Ci.nsIDOMStorageManager);
       let window = aDocShell.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindow);