diff --git a/caps/BasePrincipal.cpp b/caps/BasePrincipal.cpp
index cc32b9ca22788..a1372f4584bc9 100644
--- a/caps/BasePrincipal.cpp
+++ b/caps/BasePrincipal.cpp
@@ -71,6 +71,17 @@ BasePrincipal::GetHostPort(nsACString& aRes) {
   return prinURI->GetHostPort(aRes);
 }
 
+NS_IMETHODIMP
+BasePrincipal::GetHost(nsACString& aRes) {
+  aRes.Truncate();
+  nsCOMPtr<nsIURI> prinURI;
+  nsresult rv = GetURI(getter_AddRefs(prinURI));
+  if (NS_FAILED(rv) || !prinURI) {
+    return NS_OK;
+  }
+  return prinURI->GetHost(aRes);
+}
+
 NS_IMETHODIMP
 BasePrincipal::GetOriginNoSuffix(nsACString& aOrigin) {
   MOZ_ASSERT(mInitialized);
diff --git a/caps/BasePrincipal.h b/caps/BasePrincipal.h
index c1fbb2f78f58f..e62174629b0fa 100644
--- a/caps/BasePrincipal.h
+++ b/caps/BasePrincipal.h
@@ -129,6 +129,7 @@ class BasePrincipal : public nsJSPrincipals {
   NS_IMETHOD GetAsciiSpec(nsACString& aSpec) override;
   NS_IMETHOD GetExposablePrePath(nsACString& aResult) override;
   NS_IMETHOD GetHostPort(nsACString& aRes) override;
+  NS_IMETHOD GetHost(nsACString& aRes) override;
   NS_IMETHOD GetPrepath(nsACString& aResult) override;
   NS_IMETHOD GetOriginSuffix(nsACString& aOriginSuffix) final;
   NS_IMETHOD GetIsOnion(bool* aIsOnion) override;
diff --git a/caps/nsIPrincipal.idl b/caps/nsIPrincipal.idl
index 205b31b9ac988..51fd6c9d749dd 100644
--- a/caps/nsIPrincipal.idl
+++ b/caps/nsIPrincipal.idl
@@ -230,6 +230,12 @@ interface nsIPrincipal : nsISerializable
     [noscript] readonly attribute ACString asciiHost;
 
 
+    /**
+     * Returns the "host" portion of the 
+     * Principals URI, if any.
+     */
+    [noscript] readonly attribute ACString host;
+
     /**
         * Returns the prepath of the principals uri
         * follows the format scheme:
diff --git a/dom/storage/StorageObserver.cpp b/dom/storage/StorageObserver.cpp
index e68b1704062d1..65fcb35d6ed35 100644
--- a/dom/storage/StorageObserver.cpp
+++ b/dom/storage/StorageObserver.cpp
@@ -265,14 +265,8 @@ StorageObserver::Observe(nsISupports* aSubject, const char* aTopic,
     BasePrincipal::Cast(principal)->OriginAttributesRef().CreateSuffix(
         originSuffix);
 
-    nsCOMPtr<nsIURI> origin;
-    principal->GetURI(getter_AddRefs(origin));
-    if (!origin) {
-      return NS_OK;
-    }
-
     nsAutoCString host;
-    origin->GetHost(host);
+    principal->GetHost(host);
     if (host.IsEmpty()) {
       return NS_OK;
     }