There are two tags which have the same meaning:
What do you think?
updating post history, 20 rows affected
updating posts, 18 rows affected
updating PostTags associations, 15 rows affected
removing/renaming old tag, 1 rows affected
updating count for master tag, 1 rows affected
tag remapping of [user-interface] and [ui] complete!
remapping 0 synonyms
0 favorite and ignored tags remapped!
Tag Synonym ui -> user-interface was approved!