Enter in search box of picker dialog closes dialog

When I hit "enter" in the search box of a picker dialog, the dialog closes instead of performing a search. That's pretty annoying: every user will expect to search on enter.

Steps to reproduce:

1. Edit a document with a rich text field in it
2. Create an internal link: the "Document Picker" dialog will open
3. Enter some text in the "Search" field and hit Enter

Expected: only documents matching the search text are shown

Actual: the dialog is closed

The only way to really search is by clicking the tiny "search" icon next to the search field. Meh.

I've reproduced this issue in 12.5. It seems to be fixed already in 13.0.