I just assisted a user in the help chatroom with this issue.
Since the homepage (xat.com) conversion of html5 occurred, the chat list on the "popular" and "supporter" tabs are not updated to the appropriate language when you change your language via xat.com/language , nor is the homepage itself changed to the appropriate language.
I assume this is yet to come in the future, or perhaps xat.com/language does not work with html5 version.
Regardless, this user Is trying to assign (Supporter) to his chat [ he has 8 of them assigned] and it is not displaying in the supporters tab on the Spanish homepage of xat.
Not really sure how else to explain, if you need additional information please let me know and I can try to explain better.
check Xats homepage