diff --git a/browser/modules/PermissionUI.jsm b/browser/modules/PermissionUI.jsm
index dbf2aefa6654..11f32f13184a 100644
--- a/browser/modules/PermissionUI.jsm
+++ b/browser/modules/PermissionUI.jsm
@@ -363,10 +363,8 @@ var PermissionPromptPrototype = {
                                   this.permissionKey,
                                   promptAction.action,
                                   scope);
-            } else if (promptAction.action == SitePermissions.BLOCK ||
-                       SitePermissions.permitTemporaryAllow(this.permissionKey)) {
-              // Temporarily store BLOCK permissions only unless permission object
-              // sets permitTemporaryAllow: true
+            } else if (promptAction.action == SitePermissions.BLOCK) {
+              // Temporarily store BLOCK permissions only
               // SitePermissions does not consider subframes when storing temporary
               // permissions on a tab, thus storing ALLOW could be exploited.
               SitePermissions.set(this.principal.URI,
diff --git a/browser/modules/SitePermissions.jsm b/browser/modules/SitePermissions.jsm
index 6063c4015e1b..5f2a976219a3 100644
--- a/browser/modules/SitePermissions.jsm
+++ b/browser/modules/SitePermissions.jsm
@@ -400,23 +400,6 @@ var SitePermissions = {
     return this._defaultPrefBranch.getIntPref(permissionID, this.UNKNOWN);
   },
 
-  /*
-   * Return whether SitePermissions is permitted to store a TEMPORARY ALLOW
-   * state for a particular permission.
-   *
-   * @param {string} permissionID
-   *        The ID to get the state for.
-   *
-   * @return boolean Whether storing TEMPORARY ALLOW is permitted.
-   */
-  permitTemporaryAllow(permissionID) {
-    if (permissionID in gPermissionObject &&
-        gPermissionObject[permissionID].permitTemporaryAllow)
-      return gPermissionObject[permissionID].permitTemporaryAllow;
-
-    return false;
-  },
-
   /**
    * Returns the state and scope of a particular permission for a given URI.
    *
@@ -522,7 +505,7 @@ var SitePermissions = {
       // If you ever consider removing this line, you likely want to implement
       // a more fine-grained TemporaryPermissions that temporarily blocks for the
       // entire browser, but temporarily allows only for specific frames.
-      if (state != this.BLOCK && !this.permitTemporaryAllow(permissionID)) {
+      if (state != this.BLOCK) {
         throw "'Block' is the only permission we can save temporarily on a browser";
       }
 
@@ -712,7 +695,6 @@ var gPermissionObject = {
 
   "autoplay-media": {
     exactHostMatch: true,
-    permitTemporaryAllow: true,
     getDefault() {
       let state = Services.prefs.getIntPref("media.autoplay.default",
                                             Ci.nsIAutoplay.BLOCKED);
diff --git a/browser/modules/test/browser/browser_SitePermissions.js b/browser/modules/test/browser/browser_SitePermissions.js
index 21c981cab78b..94121c622682 100644
--- a/browser/modules/test/browser/browser_SitePermissions.js
+++ b/browser/modules/test/browser/browser_SitePermissions.js
@@ -19,32 +19,6 @@ add_task(async function testTempAllowThrows() {
   });
 });
 
-// Tests that we can set TEMPORARY ALLOW permissions for autoplay-media
-add_task(async function testTempAutoplayAllowed() {
-  Services.prefs.setIntPref("media.autoplay.default", 2);
-
-  let uri = Services.io.newURI("https://example.com");
-  let permId = "autoplay-media";
-
-  let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, uri.spec);
-
-  SitePermissions.set(uri, permId, SitePermissions.ALLOW,
-                      SitePermissions.SCOPE_TEMPORARY, tab.linkedBrowser);
-
-  let permissions = SitePermissions.getAllPermissionDetailsForBrowser(tab.linkedBrowser);
-
-  let autoplay = permissions.find(({id}) => id === "autoplay-media");
-  Assert.deepEqual(autoplay, {
-    id: "autoplay-media",
-    label: "Automatically Play Media with Sound",
-    state: SitePermissions.ALLOW,
-    scope: SitePermissions.SCOPE_TEMPORARY,
-  });
-
-  Services.prefs.clearUserPref("media.autoplay.default");
-  BrowserTestUtils.removeTab(gBrowser.selectedTab);
-});
-
 // This tests the SitePermissions.getAllPermissionDetailsForBrowser function.
 add_task(async function testGetAllPermissionDetailsForBrowser() {
   let uri = Services.io.newURI("https://example.com");