diff --git a/dom/base/nsGlobalWindowInner.cpp b/dom/base/nsGlobalWindowInner.cpp
index 9b376d581979..a13a455d78c4 100644
--- a/dom/base/nsGlobalWindowInner.cpp
+++ b/dom/base/nsGlobalWindowInner.cpp
@@ -4510,13 +4510,7 @@ Storage* nsGlobalWindowInner::GetLocalStorage(ErrorResult& aError) {
   }
 
   if (access == StorageAccess::eDeny) {
-    if (mDoc && (mDoc->GetSandboxFlags() & SANDBOXED_ORIGIN) != 0) {
-      // Only raise the exception if we are denying storage access due to
-      // sandbox restrictions.  If we're denying storage access due to other
-      // reasons (e.g. cookie policy enforcement), withhold raising the
-      // exception in an effort to achieve more web compatibility.
-      aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
-    }
+    aError.Throw(NS_ERROR_DOM_SECURITY_ERR);
     return nullptr;
   }
 
diff --git a/dom/tests/mochitest/localstorage/frameLocalStorageCookieSettings.html b/dom/tests/mochitest/localstorage/frameLocalStorageCookieSettings.html
index 451c90c3925c..996927ca84e8 100644
--- a/dom/tests/mochitest/localstorage/frameLocalStorageCookieSettings.html
+++ b/dom/tests/mochitest/localstorage/frameLocalStorageCookieSettings.html
@@ -7,9 +7,9 @@
 <script type="text/javascript">
   try {
     localStorage.setItem("contentkey", "test-value");
-    ok(false, "Setting localStorageItem should throw a type error exception");
+    ok(false, "Setting localStorageItem should throw a security exception");
   } catch(ex) {
-    is(ex.name, "TypeError");
+    is(ex.name, "SecurityError");
   }
 </script>
 </body>
diff --git a/dom/tests/mochitest/localstorage/test_localStorageCookieSettings.html b/dom/tests/mochitest/localstorage/test_localStorageCookieSettings.html
index 733d65d19133..aded2321a240 100644
--- a/dom/tests/mochitest/localstorage/test_localStorageCookieSettings.html
+++ b/dom/tests/mochitest/localstorage/test_localStorageCookieSettings.html
@@ -26,7 +26,7 @@ function test1() {
       ok(false, "Setting localStorageItem should throw a security exception");
     }
     catch(ex) {
-      is(ex.name, "TypeError");
+      is(ex.name, "SecurityError");
     }
 
     w.close();
diff --git a/toolkit/components/antitracking/test/browser/browser_blockingLocalStorage.js b/toolkit/components/antitracking/test/browser/browser_blockingLocalStorage.js
index 90392ab5aea7..e58a1ccbc71b 100644
--- a/toolkit/components/antitracking/test/browser/browser_blockingLocalStorage.js
+++ b/toolkit/components/antitracking/test/browser/browser_blockingLocalStorage.js
@@ -3,13 +3,12 @@
 AntiTracking.runTestInNormalAndPrivateMode(
   "localStorage",
   async _ => {
-    is(window.localStorage, null, "LocalStorage is null");
     try {
       localStorage.foo = 42;
       ok(false, "LocalStorage cannot be used!");
     } catch (e) {
       ok(true, "LocalStorage cannot be used!");
-      is(e.name, "TypeError", "We want a type error message.");
+      is(e.name, "SecurityError", "We want a security error message.");
     }
   },
   async _ => {
@@ -31,13 +30,12 @@ AntiTracking.runTestInNormalAndPrivateMode(
     /* import-globals-from storageAccessAPIHelpers.js */
     await noStorageAccessInitially();
 
-    is(window.localStorage, null, "LocalStorage is null");
     try {
       localStorage.foo = 42;
       ok(false, "LocalStorage cannot be used!");
     } catch (e) {
       ok(true, "LocalStorage cannot be used!");
-      is(e.name, "TypeError", "We want a type error message.");
+      is(e.name, "SecurityError", "We want a security error message.");
     }
 
     /* import-globals-from storageAccessAPIHelpers.js */
@@ -51,13 +49,12 @@ AntiTracking.runTestInNormalAndPrivateMode(
         SpecialPowers.Services.prefs.getIntPref("network.cookie.cookieBehavior")
       )
     ) {
-      is(window.localStorage, null, "LocalStorage is null");
       try {
         localStorage.foo = 42;
         ok(false, "LocalStorage cannot be used!");
       } catch (e) {
         ok(true, "LocalStorage cannot be used!");
-        is(e.name, "TypeError", "We want a type error message.");
+        is(e.name, "SecurityError", "We want a security error message.");
       }
     } else {
       localStorage.foo = 42;
diff --git a/toolkit/components/antitracking/test/browser/browser_blockingNoOpener.js b/toolkit/components/antitracking/test/browser/browser_blockingNoOpener.js
index a7b748630e2b..99c7d2bcdd5b 100644
--- a/toolkit/components/antitracking/test/browser/browser_blockingNoOpener.js
+++ b/toolkit/components/antitracking/test/browser/browser_blockingNoOpener.js
@@ -5,13 +5,12 @@ gFeatures = "noopener";
 AntiTracking.runTestInNormalAndPrivateMode(
   "Blocking in the case of noopener windows",
   async _ => {
-    is(window.localStorage, null, "LocalStorage is null");
     try {
       localStorage.foo = 42;
       ok(false, "LocalStorage cannot be used!");
     } catch (e) {
       ok(true, "LocalStorage cannot be used!");
-      is(e.name, "TypeError", "We want a type error message.");
+      is(e.name, "SecurityError", "We want a security error message.");
     }
   },
   async phase => {
@@ -21,13 +20,12 @@ AntiTracking.runTestInNormalAndPrivateMode(
         ok(true, "LocalStorage is allowed");
         break;
       case 2:
-        is(window.localStorage, null, "LocalStorage is null");
         try {
           localStorage.foo = 42;
           ok(false, "LocalStorage cannot be used!");
         } catch (e) {
           ok(true, "LocalStorage cannot be used!");
-          is(e.name, "TypeError", "We want a type error message.");
+          is(e.name, "SecurityError", "We want a security error message.");
         }
         break;
     }
diff --git a/toolkit/components/antitracking/test/browser/browser_partitionedLocalStorage.js b/toolkit/components/antitracking/test/browser/browser_partitionedLocalStorage.js
index d305696e27ac..e2ef79af9158 100644
--- a/toolkit/components/antitracking/test/browser/browser_partitionedLocalStorage.js
+++ b/toolkit/components/antitracking/test/browser/browser_partitionedLocalStorage.js
@@ -14,11 +14,6 @@ AntiTracking.runTestInNormalAndPrivateMode(
       SpecialPowers.Services.prefs.getIntPref("network.cookie.cookieBehavior")
     );
 
-    is(
-      window.localStorage == null,
-      shouldThrow,
-      shouldThrow ? "LocalStorage is null" : "LocalStorage is not null"
-    );
     let hasThrown;
     try {
       localStorage.foo = 42;
@@ -26,7 +21,7 @@ AntiTracking.runTestInNormalAndPrivateMode(
       is(localStorage.foo, "42", "The value matches");
       hasThrown = false;
     } catch (e) {
-      is(e.name, "TypeError", "We want a type error message.");
+      is(e.name, "SecurityError", "We want a security error message.");
       hasThrown = true;
     }
 
diff --git a/toolkit/components/antitracking/test/browser/browser_script.js b/toolkit/components/antitracking/test/browser/browser_script.js
index 6ef9e15c5f38..8312f725d6b5 100644
--- a/toolkit/components/antitracking/test/browser/browser_script.js
+++ b/toolkit/components/antitracking/test/browser/browser_script.js
@@ -39,13 +39,12 @@ add_task(async function() {
     async obj => {
       info("Checking if permission is denied");
       let callbackBlocked = async _ => {
-        is(window.localStorage, null, "LocalStorage is null");
         try {
           localStorage.foo = 42;
           ok(false, "LocalStorage cannot be used!");
         } catch (e) {
           ok(true, "LocalStorage cannot be used!");
-          is(e.name, "TypeError", "We want a type error message.");
+          is(e.name, "SecurityError", "We want a security error message.");
         }
       };
 
@@ -112,13 +111,12 @@ add_task(async function() {
     async obj => {
       info("Checking if permission is denied");
       let callbackBlocked = async _ => {
-        is(window.localStorage, null, "LocalStorage is null");
         try {
           localStorage.foo = 42;
           ok(false, "LocalStorage cannot be used!");
         } catch (e) {
           ok(true, "LocalStorage cannot be used!");
-          is(e.name, "TypeError", "We want a type error message.");
+          is(e.name, "SecurityError", "We want a security error message.");
         }
       };
 
diff --git a/toolkit/components/antitracking/test/browser/browser_siteSpecificWorkArounds.js b/toolkit/components/antitracking/test/browser/browser_siteSpecificWorkArounds.js
index 3a92c99743bf..053aa91bf91b 100644
--- a/toolkit/components/antitracking/test/browser/browser_siteSpecificWorkArounds.js
+++ b/toolkit/components/antitracking/test/browser/browser_siteSpecificWorkArounds.js
@@ -84,13 +84,12 @@ AntiTracking.runTest(
 AntiTracking.runTest(
   "localStorage with a tracker that is whitelisted via a misconfigured pref",
   async _ => {
-    is(window.localStorage, null, "LocalStorage is null");
     try {
       localStorage.foo = 42;
       ok(false, "LocalStorage cannot be used!");
     } catch (e) {
       ok(true, "LocalStorage cannot be used!");
-      is(e.name, "TypeError", "We want a type error message.");
+      is(e.name, "SecurityError", "We want a security error message.");
     }
   },
   async _ => {
diff --git a/toolkit/components/antitracking/test/browser/browser_storageAccessSandboxed.js b/toolkit/components/antitracking/test/browser/browser_storageAccessSandboxed.js
index 9a30fffff09a..2c9b7e3df817 100644
--- a/toolkit/components/antitracking/test/browser/browser_storageAccessSandboxed.js
+++ b/toolkit/components/antitracking/test/browser/browser_storageAccessSandboxed.js
@@ -60,13 +60,12 @@ AntiTracking.runTest(
     /* import-globals-from storageAccessAPIHelpers.js */
     await noStorageAccessInitially();
 
-    is(window.localStorage, null, "LocalStorage is null");
     try {
       localStorage.foo = 42;
       ok(false, "LocalStorage cannot be used!");
     } catch (e) {
       ok(true, "LocalStorage cannot be used!");
-      is(e.name, "TypeError", "We want a type error message.");
+      is(e.name, "SecurityError", "We want a security error message.");
     }
   },
 
@@ -110,13 +109,12 @@ AntiTracking.runTest(
     /* import-globals-from storageAccessAPIHelpers.js */
     await noStorageAccessInitially();
 
-    is(window.localStorage, null, "LocalStorage is null");
     try {
       localStorage.foo = 42;
       ok(false, "LocalStorage cannot be used!");
     } catch (e) {
       ok(true, "LocalStorage cannot be used!");
-      is(e.name, "TypeError", "We want a type error message.");
+      is(e.name, "SecurityError", "We want a security error message.");
     }
   },
 
diff --git a/toolkit/components/extensions/test/xpcshell/test_ext_cookieBehaviors.js b/toolkit/components/extensions/test/xpcshell/test_ext_cookieBehaviors.js
index 44da7ce8654e..cf1d7bdbedf0 100644
--- a/toolkit/components/extensions/test/xpcshell/test_ext_cookieBehaviors.js
+++ b/toolkit/components/extensions/test/xpcshell/test_ext_cookieBehaviors.js
@@ -553,8 +553,9 @@ add_task(async function test_content_script_on_cookieBehaviorReject() {
       "a content script can't use indexedDB from a page where it is disallowed"
     );
 
-    browser.test.assertTrue(
-      window.localStorage === null,
+    browser.test.assertThrows(
+      () => localStorage,
+      /The operation is insecure/,
       "a content script can't use localStorage from a page where it is disallowed"
     );