box for hidden field invisible

I’ve got a few hidden fields in my PDB records. I cannnot add information for these hidden fields any more, because the box for adding content has disappeared: only on records where some information has already been added to this field, the box is visible, otherwise there is just nothing after the title/label on the backend.

I don’t know exactly when this occurred, these hidden fields are not used very often. As far as I can see, the last record where a hidden field was used, was changed on june 1. Could this be related to one of the recent updates?

I hope this can be solved soon.