Changes and/or original content of a document are not shown in preview

Reproducible by "Stability tests":

• With a number of users (unclear if this is a requirement)
• Open a document
• Change the document, Save & Close
• Click "View" and choose the channel
  Expected result: The newly changed content is shown
  Actual result: Not all content is shown, or document can't be found at all
  A search for the document will yield the result, but it can't be accessed

Issue doesn't surface when performing a publication prior to viewing the document in the channel.
Workaround (when detected): Open the document for editing and save it again.

Reproducibility: About 1 in 10 of the above sequences

Priority rationale: schrijvers recommended Blocker prio