[vine] Relax `alt_title` (Closes #5677)

diff --git a/youtube_dl/extractor/vine.py b/youtube_dl/extractor/vine.py
index 65c459fad39c36798d3d262d37ee95e52a2c313c..c733a48fa26edce6b219d3bf2404267b8c346bf6 100644 (file)
--- a/youtube_dl/extractor/vine.py
+++ b/youtube_dl/extractor/vine.py
@@ -75,7 +75,7 @@ class VineIE(InfoExtractor):
         return {
             'id': video_id,
             'title': self._og_search_title(webpage),
-            'alt_title': self._og_search_description(webpage),
+            'alt_title': self._og_search_description(webpage, default=None),
             'description': data['description'],
             'thumbnail': data['thumbnailUrl'],
             'upload_date': unified_strdate(data['created']),