Authors do not see any pages

Authors cannot see any pages in the 'Pages' window. Instead, they get a 'technical error' warning.

Steps to reproduce:
1. start the page management archetype
2. login as author
3. navigate to the only channel
4. click the 'Pages' button

Expected: a list of all pages is shown. Clicking a page opens it in the channel manager
Actual: a 'technical error' is shown