SOLVED: Google books no longer has Chapter menus

Apologies in advance for the long post. I know you weren't asking for a work-around, but here it is:

I downloaded a free e-book from Google Play and used it in their app, and confirmed that there is no way to call up the clickable table of contents within the app.

I opened play.google.com/books in the browser on my computer, and downloaded the e-book to my computer as an EPUB. I transferred it to my phone's internal storage, and opened the e-book in Cool Reader.

The table of contents was still inaccessible because the structure of the book was broken. I went back to my computer and opened the e-book in Sigil, and I got this message: "This EPUB has HTML files that are not well formed. Sigil can attempt to automatically fix these files ... ".

I clicked Yes, saved, and exited.

I moved the fixed e-book to my Android device's internal storage, opened it in Cool Reader, and now the clickable table of contents can be called up, and it works.