I am using MHRA2 citation style.

When I cite an item classified as a thesis, Zotero automatically adds the word ‘unpublished’ in front of the class of thesis that I provide (‘PhD thesis’ in this example):

Otte, Andrea, ‘Im Zeichen der Zukunft. Die Jungfrau im Werk von Joseph Beuys’ [Under the Sign of the Future. The Virgin in the Work of Joseph Beuys] (unpublished PhD thesis, Technische Universität Dortmund, 1998)

Can I turn off the word 'unpublished'?

The reason is that it looks odd when, as is often the case, I cite both a thesis and a later book that was based on the thesis. Using the multiple sources option, setting the prefix to ‘published as’ before the book citation, and suppressing the author, I get:

Otte, Andrea, ‘Im Zeichen der Zukunft. Die Jungfrau im Werk von Joseph Beuys’ [Under the Sign of the Future. The Virgin in the Work of Joseph Beuys] (unpublished PhD thesis, Technische Universität Dortmund, 1998); published as Die Jungfrau im Werk von Joseph Beuys [The Virgin in the Work of Joseph Beuys] (Hamburg: Norderstedt Books GmbH, 2008).

This is entirely accurate, but my proof-reader thinks it is odd to say ‘unpublished’ and then ‘published as’. I would prefer to change all thesis references to omit the word ‘unpublished’, so I would get:

Otte, Andrea, ‘Im Zeichen der Zukunft. Die Jungfrau im Werk von Joseph Beuys’ [Under the Sign of the Future. The Virgin in the Work of Joseph Beuys] (PhD thesis, Technische Universität Dortmund, 1998); published as Die Jungfrau im Werk von Joseph Beuys [The Virgin in the Work of Joseph Beuys] (Hamburg: Norderstedt Books GmbH, 2008).

Can I do that now or is a feature request needed?