Basic setting changes don't take effect in print PDF format until after several exports

[mcgratay]

Prerequisites

• [x] Can you reproduce the behavior you wish to address with all other plugins deactivated?
• [x] Are you running the latest version of Pressbooks and the latest version of WordPress?
• [x] Are you experiencing this issue with one of our built-in root or book themes?
• [x] Did you perform a cursory search to see if your bug or enhancement is already listed?

Description

Equations can be displayed in webbook and export formats using a service called QuickLaTeX. QuickLaTeX allows you to customize several settings, including position, size, text color, and background color.

Changes to these basic settings will display in the webbook immediately after they are saved. These settings will not automatically display in print PDF format, however. The first several rounds of exports after the settings are changed will not reflect the user's customizations. As an example, here is the QuickLaTeX settings page after display has been customized:

Here's the resulting webbook immediately after:

And here's a shot of this same section in the PDF from an export created after the settings were saved:

Generally, the next 2 to 3 exports will display the LaTeX with no changes. Then, you'll have an export that will take a particularly long time to complete but will eventually fail and display the following error:

However, the logs will not show any error report for the book. Eventually, the print PDF will display the setting changes. In this example it took ~7 exports.

Does not seem to affect any format but print PDF.

Example: https://latexsettingstest.textopress.com/

Steps to Reproduce

1. Go to the Plugins page to enable QuickLaTeX in your test book if it isn't already enabled
2. Create a new chapter in the book with a few LaTeX equations wrapped in [latex] shortcodes
3. Go to Settings > QuickLaTeX > Basic Settings and change some of the LaTeX display settings, then save
4. Export to print PDF and view
5. Repeat export until the LaTeX settings changes are reflected in the PDF file

Expected behavior: Saved setting changes take effect immediately in all supported book formats

Actual behavior: Saved setting changes for QuickLaTeX do not immediately appear in print PDF exports and sometimes cause unidentifiable validation errors

[beckej13820]

In my experience with QuickLaTeX, I have had to go to every single page first to make exports work. My understanding was that QuickLaTeX generates all of its files on page load, and then caches them. So if I was doing an export with QuickLaTeX, I needed to quickly scroll through every chapter first, then do the export.

Is it possible this is related?