diff --git a/youtube_dl/extractor/youtube.py b/youtube_dl/extractor/youtube.py
index 16952670d..25d056b3c 100644
--- a/youtube_dl/extractor/youtube.py
+++ b/youtube_dl/extractor/youtube.py
@@ -386,7 +386,7 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
                             (?:www\.)?invidious\.kabi\.tk/|
                             (?:www\.)?invidious\.enkirton\.net/|
                             (?:www\.)?invidious\.13ad\.de/|
-                            (?:www\.)?invidious\.mastodon\.host/| 
+                            (?:www\.)?invidious\.mastodon\.host/|
                             (?:www\.)?invidious\.nixnet\.xyz/|
                             (?:www\.)?tube\.poal\.co/|
                             (?:www\.)?vid\.wxzm\.sx/|