Oh, so it's similar to using templates in a theme, only addon ones are appended rather than replacements?

Thank you for your help! Turns out it was simpler than I thought and I was messing it up by making it overly complicated.

I've got it working now 😃 And because I moved all the settings into an array my footer.tpl is just 7 lines of code to iterate through that array.

The original purpose of this add-on was to make it easier to change/translate all the pseudo-element nav and action button labels. With all of those now moved into the core I'm not sure how useful this add-on still is, but it also gives pretty granular control over most of the Bookface CSS variables.

I'm just about finished updating Bookface for 2026.08-rc. I just need to actually install the RC on my Dev Server to check it.