[ie/youtube] Fix web_embedded player client (#16177)

Closes #16077
Authored by: SparseOrnament15, bashonly

Co-authored-by: bashonly <88596187+bashonly@users.noreply.github.com>

README.md

@@ -1880,7 +1880,7 @@ The following extractors use this feature:
 * `pot_trace`: Enable debug logging for PO Token fetching. Either `true` or `false` (default)
 * `fetch_pot`: Policy to use for fetching a PO Token from providers. One of `always` (always try fetch a PO Token regardless if the client requires one for the given context), `never` (never fetch a PO Token), or `auto` (default; only fetch a PO Token if the client requires one for the given context)
 * `jsc_trace`: Enable debug logging for JS Challenge fetching. Either `true` or `false` (default)
-* `use_ad_playback_context`: Skip preroll ads to eliminate the mandatory wait period before download. Do NOT use this when passing premium account cookies to yt-dlp, as it will result in a loss of premium formats. Only effective with the `web`, `web_safari`, `web_music` and `mweb` player clients. Either `true` or `false` (default)
+* `use_ad_playback_context`: Skip preroll ads to eliminate the mandatory wait period before download. Do NOT use this when passing premium account cookies to yt-dlp, as it will result in a loss of premium formats. Only effective with the `mweb` and `web_music` player clients. Either `true` or `false` (default)
 
 #### youtube-ejs
 * `jitless`: Run supported Javascript engines in JIT-less mode. Supported runtimes are `deno`, `node` and `bun`. Provides better security at the cost of performance/speed. Do note that `node` and `bun` are still considered insecure. Either `true` or `false` (default)

yt_dlp/extractor/youtube/_base.py

@@ -104,7 +104,6 @@ INNERTUBE_CLIENTS = {
         },
         'INNERTUBE_CONTEXT_CLIENT_NAME': 1,
         'SUPPORTS_COOKIES': True,
-        'SUPPORTS_AD_PLAYBACK_CONTEXT': True,
         **WEB_PO_TOKEN_POLICIES,
     },
     # Safari UA returns pre-merged video+audio 144p/240p/360p/720p/1080p HLS formats
@@ -118,7 +117,6 @@ INNERTUBE_CLIENTS = {
         },
         'INNERTUBE_CONTEXT_CLIENT_NAME': 1,
         'SUPPORTS_COOKIES': True,
-        'SUPPORTS_AD_PLAYBACK_CONTEXT': True,
         **WEB_PO_TOKEN_POLICIES,
     },
     'web_embedded': {
@@ -223,16 +221,17 @@ INNERTUBE_CLIENTS = {
         },
         'PLAYER_PO_TOKEN_POLICY': PlayerPoTokenPolicy(required=False, recommended=True),
     },
-    # YouTube Kids videos aren't returned on this client for some reason
+    # "Made for kids" videos aren't available with this client
+    # Using a clientVersion>1.65 may return SABR streams only
     'android_vr': {
         'INNERTUBE_CONTEXT': {
             'client': {
                 'clientName': 'ANDROID_VR',
-                'clientVersion': '1.71.26',
+                'clientVersion': '1.65.10',
                 'deviceMake': 'Oculus',
                 'deviceModel': 'Quest 3',
                 'androidSdkVersion': 32,
-                'userAgent': 'com.google.android.apps.youtube.vr.oculus/1.71.26 (Linux; U; Android 12L; eureka-user Build/SQ3A.220605.009.A1) gzip',
+                'userAgent': 'com.google.android.apps.youtube.vr.oculus/1.65.10 (Linux; U; Android 12L; eureka-user Build/SQ3A.220605.009.A1) gzip',
                 'osName': 'Android',
                 'osVersion': '12L',
             },
@@ -369,7 +368,7 @@ def short_client_name(client_name):
 
 def _fix_embedded_ytcfg(ytcfg):
     ytcfg['INNERTUBE_CONTEXT'].setdefault('thirdParty', {}).update({
-        'embedUrl': 'https://www.youtube.com/',  # Can be any valid URL
+        'embedUrl': 'https://www.reddit.com/',  # Can be any valid non-YouTube URL
     })
 
 
@@ -968,6 +967,7 @@ class YoutubeBaseInfoExtractor(InfoExtractor):
             url, video_id, note=f'Downloading {client.replace("_", " ").strip()} client config',
             headers=traverse_obj(self._get_default_ytcfg(client), {
                 'User-Agent': ('INNERTUBE_CONTEXT', 'client', 'userAgent', {str}),
+                'Referer': ('INNERTUBE_CONTEXT', 'thirdParty', 'embedUrl', {str}),
             }))
 
         ytcfg = self.extract_ytcfg(video_id, webpage) or {}

yt_dlp/extractor/youtube/_video.py

@@ -2680,12 +2680,14 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
         return {'contentCheckOk': True, 'racyCheckOk': True}
 
     @classmethod
-    def _generate_player_context(cls, sts=None, use_ad_playback_context=False):
+    def _generate_player_context(cls, sts=None, use_ad_playback_context=False, encrypted_context=None):
         context = {
             'html5Preference': 'HTML5_PREF_WANTS',
         }
         if sts is not None:
             context['signatureTimestamp'] = sts
+        if encrypted_context:
+            context['encryptedHostFlags'] = encrypted_context
 
         playback_context = {
             'contentPlaybackContext': context,
@@ -2930,7 +2932,19 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
             self._configuration_arg('use_ad_playback_context', ['false'])[0] != 'false'
             and traverse_obj(INNERTUBE_CLIENTS, (client, 'SUPPORTS_AD_PLAYBACK_CONTEXT', {bool})))
 
-        yt_query.update(self._generate_player_context(sts, use_ad_playback_context))
+        # web_embedded player requests may need to include encryptedHostFlags in its contentPlaybackContext.
+        # This can be detected with the embeds_enable_encrypted_host_flags_enforcement experiemnt flag,
+        # but there is no harm in including encryptedHostFlags with all web_embedded player requests.
+        encrypted_context = None
+        if client == 'web_embedded':
+            encrypted_context = traverse_obj(player_ytcfg, (
+                'WEB_PLAYER_CONTEXT_CONFIGS', 'WEB_PLAYER_CONTEXT_CONFIG_ID_EMBEDDED_PLAYER', 'encryptedHostFlags'))
+
+        yt_query.update(
+            self._generate_player_context(
+                sts=sts,
+                use_ad_playback_context=use_ad_playback_context,
+                encrypted_context=encrypted_context))
 
         return self._extract_response(
             item_id=video_id, ep='player', query=yt_query,