After Confluence Cloud was upgraded to 5.7-OD-42, the contributors macro stopped working properly. Not all watchers are added, even thought 'watchers' is selected.

Steps to reproduce

• Have a 5.7-OD-42 Confluence Cloud instance (only tested in JIRA+Confluence ones)
• Create a page (you should be automatically added as watcher, if not, do it)
• Add the contributors macro to it
  • Contribution type:

    authors,comments,mentions,watches
    

    • Leaving only 'watches' also reproduces the problem
  • Sort by: name
  • Display format: list
  • The rest is empty

Expected result

• The page's author should be part of the list
  • (S)he is both author and watcher

Actual Result

• The following message:

  No contributors found for: watches on selected page(s)
  

Sometimes, when changing the macro and saving it. It starts working for no reason.

Reports seem to indicate that it worked before the upgrade.