Students from almost all countries in Africa and The Middle East, and Cyprus, have to now provide a long list of documents to extend their student visas for another year (as opposed to just a copy of your passport, a picture and the standard uni docs) Not sure if this is for all universities across the board, or only government unis, but this list was distributed by Ramkhamhaeng University, effective from 22 June.

Has anyone had any experience with this at immigration?

Seems that the Authorities wish to assure themselves that "students" have no criminal record either in Thailand or their country of origin.

In addition assurance of income derived from outside Thailand is sought to reduce fears of income being obtained as a result of illegal work.

If this is ,in fact , a new set of requirements one can only surmise that the Authorities have good reason for requesting the documentation.