--- a/caps/BasePrincipal.cpp
+++ b/caps/BasePrincipal.cpp
@@ -353,32 +353,16 @@ NS_IMETHODIMP
 BasePrincipal::EqualsConsideringDomain(nsIPrincipal *aOther, bool *aResult)
 {
   NS_ENSURE_TRUE(aOther, NS_ERROR_INVALID_ARG);
   *aResult = Subsumes(aOther, ConsiderDocumentDomain) &&
              Cast(aOther)->Subsumes(this, ConsiderDocumentDomain);
   return NS_OK;
 }
 
-bool
-BasePrincipal::EqualsIgnoringAddonId(nsIPrincipal *aOther)
-{
-  MOZ_ASSERT(aOther);
-
-  // Note that this will not work for expanded principals, nor is it intended
-  // to.
-  if (!dom::ChromeUtils::IsOriginAttributesEqualIgnoringAddonId(
-          OriginAttributesRef(), Cast(aOther)->OriginAttributesRef())) {
-    return false;
-  }
-
-  return SubsumesInternal(aOther, DontConsiderDocumentDomain) &&
-         Cast(aOther)->SubsumesInternal(this, DontConsiderDocumentDomain);
-}
-
 NS_IMETHODIMP
 BasePrincipal::Subsumes(nsIPrincipal *aOther, bool *aResult)
 {
   NS_ENSURE_TRUE(aOther, NS_ERROR_INVALID_ARG);
   *aResult = Subsumes(aOther, DontConsiderDocumentDomain);
   return NS_OK;
 }
 

--- a/caps/BasePrincipal.h
+++ b/caps/BasePrincipal.h
@@ -244,18 +244,16 @@ public:
   NS_IMETHOD GetOriginSuffix(nsACString& aOriginSuffix) final;
   NS_IMETHOD GetAppStatus(uint16_t* aAppStatus) final;
   NS_IMETHOD GetAppId(uint32_t* aAppStatus) final;
   NS_IMETHOD GetIsInIsolatedMozBrowserElement(bool* aIsInIsolatedMozBrowserElement) final;
   NS_IMETHOD GetUnknownAppId(bool* aUnknownAppId) final;
   NS_IMETHOD GetUserContextId(uint32_t* aUserContextId) final;
   NS_IMETHOD GetPrivateBrowsingId(uint32_t* aPrivateBrowsingId) final;
 
-  bool EqualsIgnoringAddonId(nsIPrincipal *aOther);
-
   virtual bool AddonHasPermission(const nsAString& aPerm);
 
   virtual bool IsCodebasePrincipal() const { return false; };
 
   static BasePrincipal* Cast(nsIPrincipal* aPrin) { return static_cast<BasePrincipal*>(aPrin); }
   static already_AddRefed<BasePrincipal>
   CreateCodebasePrincipal(nsIURI* aURI, const OriginAttributes& aAttrs);
   static already_AddRefed<BasePrincipal> CreateCodebasePrincipal(const nsACString& aOrigin);

--- a/dom/base/ChromeUtils.cpp
+++ b/dom/base/ChromeUtils.cpp
@@ -185,30 +185,19 @@ ChromeUtils::IsOriginAttributesEqual(con
   return aA.mAddonId == aB.mAddonId &&
          aA.mAppId == aB.mAppId &&
          aA.mInIsolatedMozBrowser == aB.mInIsolatedMozBrowser &&
          aA.mUserContextId == aB.mUserContextId &&
          aA.mPrivateBrowsingId == aB.mPrivateBrowsingId;
 }
 
 /* static */ bool
-ChromeUtils::IsOriginAttributesEqualIgnoringAddonId(const dom::OriginAttributesDictionary& aA,
-                                                    const dom::OriginAttributesDictionary& aB)
+ChromeUtils::IsOriginAttributesEqualIgnoringFPD(const dom::OriginAttributesDictionary& aA,
+                                                const dom::OriginAttributesDictionary& aB)
 {
   return aA.mAppId == aB.mAppId &&
          aA.mInIsolatedMozBrowser == aB.mInIsolatedMozBrowser &&
          aA.mUserContextId == aB.mUserContextId &&
          aA.mPrivateBrowsingId == aB.mPrivateBrowsingId;
 }
 
-/* static */ bool
-ChromeUtils::IsOriginAttributesEqualIgnoringFPD(const dom::OriginAttributesDictionary& aA,
-                                                const dom::OriginAttributesDictionary& aB)
-{
-  return aA.mAddonId == aB.mAddonId &&
-         aA.mAppId == aB.mAppId &&
-         aA.mInIsolatedMozBrowser == aB.mInIsolatedMozBrowser &&
-         aA.mUserContextId == aB.mUserContextId &&
-         aA.mPrivateBrowsingId == aB.mPrivateBrowsingId;
-}
-
 } // namespace dom
 } // namespace mozilla

--- a/dom/base/ChromeUtils.h
+++ b/dom/base/ChromeUtils.h
@@ -88,20 +88,16 @@ public:
                           const dom::OriginAttributesDictionary& aA,
                           const dom::OriginAttributesDictionary& aB);
 
   static bool
   IsOriginAttributesEqual(const dom::OriginAttributesDictionary& aA,
                           const dom::OriginAttributesDictionary& aB);
 
   static bool
-  IsOriginAttributesEqualIgnoringAddonId(const dom::OriginAttributesDictionary& aA,
-                                         const dom::OriginAttributesDictionary& aB);
-
-  static bool
   IsOriginAttributesEqualIgnoringFPD(const dom::OriginAttributesDictionary& aA,
                                      const dom::OriginAttributesDictionary& aB);
 };
 
 } // namespace dom
 } // namespace mozilla
 
 #endif // mozilla_dom_ChromeUtils__