Do not block large media resources when loaded as top-level document

Related issues:
- uBlockOrigin/uBlock-issues#1201
- uBlockOrigin/uBlock-issues#3184

Top-level media resources are not meant to be blocked, see:
#2813 (comment)

src/js/pagestore.js

@@ -19,29 +19,27 @@
     Home: https://github.com/gorhill/uBlock
 */
 
-'use strict';
-
 /******************************************************************************/
 
-import contextMenu from './contextmenu.js';
-import logger from './logger.js';
-import staticNetFilteringEngine from './static-net-filtering.js';
-import µb from './background.js';
-import webext from './webext.js';
-import { orphanizeString } from './text-utils.js';
-import { redirectEngine } from './redirect-engine.js';
+import {
+    domainFromHostname,
+    hostnameFromURI,
+    isNetworkURI,
+} from './uri-utils.js';
 
 import {
     sessionFirewall,
     sessionSwitches,
     sessionURLFiltering,
 } from './filtering-engines.js';
 
-import {
-    domainFromHostname,
-    hostnameFromURI,
-    isNetworkURI,
-} from './uri-utils.js';
+import contextMenu from './contextmenu.js';
+import logger from './logger.js';
+import { orphanizeString } from './text-utils.js';
+import { redirectEngine } from './redirect-engine.js';
+import staticNetFilteringEngine from './static-net-filtering.js';
+import webext from './webext.js';
+import µb from './background.js';
 
 /*******************************************************************************
 
@@ -379,11 +377,13 @@ const PageStore = class {
 
         // If we are navigating from-to same site, remember whether large
         // media elements were temporarily allowed.
-        if (
-            typeof this.allowLargeMediaElementsUntil !== 'number' ||
-            tabContext.rootHostname !== this.tabHostname
-        ) {
-            this.allowLargeMediaElementsUntil = Date.now();
+        const now = Date.now();
+        if ( typeof this.allowLargeMediaElementsUntil !== 'number' ) {
+            this.allowLargeMediaElementsUntil = now;
+        } else if ( tabContext.rootHostname !== this.tabHostname ) {
+            if ( this.tabHostname.endsWith('about-scheme') === false ) {
+                this.allowLargeMediaElementsUntil = now;
+            }
         }
 
         this.tabHostname = tabContext.rootHostname;

src/js/traffic.js

@@ -590,7 +590,7 @@ const onHeadersReceived = function(details) {
     }
 };
 
-const reMediaContentTypes = /^(?:audio|image|video)\//;
+const reMediaContentTypes = /^(?:audio|image|video)\/|(?:\/ogg)$/;
 
 /******************************************************************************/