Tables expand beyond page limits in some common ereader software

[mcgratay]

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

The HTML and CSS used to build tables isn't compatible with Adobe Digital Editions, a common ereading software that's used to support the ebook services of Nook, Kobo, and other ebook distribution services. In ADE, tables widths will often exceed the width of the page. In the image below, you can see that the last column on the previous page and the first column on the next page overlap, making those tables hard to read. You can also see that the last column on the second page is cut off because it's overflowing past the margins:

Tables left at the default width of 100% should always match the margins of the text. Note in the image below that tables with as few two columns expand past that right margin:

Issue is unaffected by table class, book theme, or alignment. Issues are prevalent in most tested softwares (Adobe Digital Editions, Firefox, Chrome), with notable exception of iBooks. MOBIs do not seem to share the same problem. Lowering the table's width using Table Properties does seem to mitigate the issue, but it is hard to predict what the right percentage is since "100%" is false.

Example: https://tables2wide4u.textopress.com/

Steps to Reproduce

1. Download Adobe Digital Editions (https://www.adobe.com/solutions/ebook/digital-editions.html)
2. Create a new chapter in Pressbooks, then add a table without changing the default width
3. Add text inside the table cells, and a paragraph below the table for comparison
4. Export to EPUB format, then download the file and open in Adobe Digital Editions
5. Compare table width to paragraph width

Expected behavior: Tables obey the margins in ebook format

Actual behavior: Tables expand beyond the margins in some common ebook readers