Search nnimap folder with 'G G' and move found articles

Using Gnus from emacs 29.3.

If I search up some articles in an nnimap group with 'G G', what's the
simplest way of moving a selection of the found articles to a different
group.

Marking the articles in the summary buffer opened by 'G G' and then
doing 'B m" fails with
 nnselect-request-group: Wrong type argument: consp, nil

Thanks!


- Steinar