http://test.musicbrainz.org/work/create
Typing in the artist box doesn't initiate searching, and clicking the button to pop out the full artist credit editor does nothing.

This also happens when creating a work with a pre-filled artist, e.g.
http://test.musicbrainz.org/work/create?artist=b10bbbfc-cf9e-42e0-be17-e2c3e1d2600d
Where you can accept the pre-filled artist, but not edit the artist credit.