As some support issues already stated, the use of wildcards when searching users, using the search plugin is not working properly.
https://community.igniterealtime.org/thread/58258
https://community.igniterealtime.org/thread/59061
Trying to find a user "abc" using query 'a' works, but when using 'a*' nothing is found. Also '*b*' or '*c' does not work.
This is probably related to this change OF-779: fetching from LDAP should escape results. All search criteria are escaped, also the wildcard characters.
I Updated the code to refine the solution of OF-779 to enable the use of wildcards again.