[youtube] Fix authentication (#10392)

youtube_dl/extractor/youtube.py

@@ -91,36 +91,17 @@ class YoutubeBaseInfoExtractor(InfoExtractor):
         if login_page is False:
             return
 
-        galx = self._search_regex(r'(?s)<input.+?name="GALX".+?value="(.+?)"',
-                                  login_page, 'Login GALX parameter')
+        login_form = self._hidden_inputs(login_page)
 
-        # Log in
-        login_form_strs = {
-            'continue': 'https://www.youtube.com/signin?action_handle_signin=true&feature=sign_in_button&hl=en_US&nomobiletemp=1',
+        login_form.update({
             'Email': username,
-            'GALX': galx,
             'Passwd': password,
-
-            'PersistentCookie': 'yes',
-            '_utf8': '霱',
-            'bgresponse': 'js_disabled',
-            'checkConnection': '',
-            'checkedDomains': 'youtube',
-            'dnConn': '',
-            'pstMsg': '0',
-            'rmShown': '1',
-            'secTok': '',
-            'signIn': 'Sign in',
-            'timeStmp': '',
-            'service': 'youtube',
-            'uilel': '3',
-            'hl': 'en_US',
-        }
+        })
 
         login_results = self._download_webpage(
             self._PASSWORD_CHALLENGE_URL, None,
             note='Logging in', errnote='unable to log in', fatal=False,
-            data=urlencode_postdata(login_form_strs))
+            data=urlencode_postdata(login_form))
         if login_results is False:
             return False