Cloning issue potentially related to math and/or imported content from OpenStax

[pb-amy]

Prerequisites

• [x] Can you reproduce the behavior you wish to address with all plugins except Pressbooks deactivated?
• [x] Are you running the latest version of Pressbooks, the latest version of McLuhan, and the latest version of WordPress?
• [x] Are you experiencing the issue while using this book theme?
• [x] Did you perform a cursory search to see if your bug or enhancement is already listed?

Description

This was an issue from this ticket.

This physics book on the openpress.usask.ca network is not cloning. It was originally brought in from OpenStax (as an import), but it doesn't seem to be cloning over any of the content; only chapter titles were imported, but no content. Further, a "cloning successful!" message shows upon completion of cloning, but it does not properly fulfill cloning.

This happened in another instance - this physics book was originally brought in from OpenStax, but upon cloning, none of the chapters were imported: https://university.pressbooks.pub/ucfcopy/

Steps to Reproduce

1. Go to this book: https://openpress.usask.ca/physics155/
2. Clone onto internal testing network.
3. Go onto Organize and see that book has not been cloned over properly.

Expected behavior: Book should complete in full.

Actual behavior: Only chapter titles are brought over (TOC elements)

System Information

[gavinpressbooks]

This issue was reproduced on both the university and integrations networks with the same behaviour as described above. In the University of Saskatchewan example, a successful cloning message was received but chapter content was not imported. The only content brought in were the various appendices at the end of the book. (https://university.pressbooks.pub/usaskphystest/)

A similar situation happened when testing the second book suggested in the original bug report was cloned, but it was only chapter summaries and one regular chapter containing the main text of the book. (https://university.pressbooks.pub/usaskphystest2/)