Add comment about weird .video extension for format 38

diff --git a/youtube-dl b/youtube-dl
index 71bf6aecc2db82200366cf194b07172579b80d75..481f9f400422149f552a490847558fb8cf43e960 100755 (executable)
--- a/youtube-dl
+++ b/youtube-dl
@@ -693,7 +693,7 @@ class YoutubeIE(InfoExtractor):
                '18': 'mp4',
                '22': 'mp4',
                '37': 'mp4',
-               '38': 'video',
+               '38': 'video', # You actually don't know if this will be MOV, AVI or whatever
                '43': 'webm',
                '45': 'webm',
        }