Fix compatibility of ManagedMediaSource implementation with Edge 18

Fixes #6243

src/controller/buffer-controller.ts

@@ -89,7 +89,10 @@ export default class BufferController implements ComponentAPI {
   constructor(hls: Hls) {
     this.hls = hls;
     const logPrefix = '[buffer-controller]';
-    this.appendSource = hls.config.preferManagedMediaSource;
+    this.appendSource =
+      hls.config.preferManagedMediaSource &&
+      typeof self !== 'undefined' &&
+      (self as any).ManagedMediaSource;
     this.log = logger.log.bind(logger, logPrefix);
     this.warn = logger.warn.bind(logger, logPrefix);
     this.error = logger.error.bind(logger, logPrefix);
@@ -345,7 +348,7 @@ export default class BufferController implements ComponentAPI {
             if (trackName.slice(0, 5) === 'audio') {
               trackCodec = getCodecCompatibleName(
                 trackCodec,
-                this.hls.config.preferManagedMediaSource,
+                this.appendSource,
               );
             }
             const mimeType = `${container};codecs=${trackCodec}`;
@@ -920,10 +923,7 @@ export default class BufferController implements ComponentAPI {
         let codec = track.levelCodec || track.codec;
         if (codec) {
           if (trackName.slice(0, 5) === 'audio') {
-            codec = getCodecCompatibleName(
-              codec,
-              this.hls.config.preferManagedMediaSource,
-            );
+            codec = getCodecCompatibleName(codec, this.appendSource);
           }
         }
         const mimeType = `${track.container};codecs=${codec}`;