I copied a page, along with 24 child pages, but the attachments that appear on the copied page do not preview properly. Both images and PDFs.
Immediately after copying, when I look at the page, the attachments are displayed correctly, but when I go into the edit screen for that page, all attachments placed on the page change to a placeholder that says "Failed to load".
Even if I save the page as it is, the "Failed to load" message does not change.

Upon checking, the above problem did not occur on about 5 of the 25 pages I copied.
Looking at the attachment list for the corrupted pages, the attachments themselves appear to be copied without any problems.
It would be nice to at least be able to place files from the attachment list into the document, but I am puzzled that I can't do that either.