The email you have sent: “Hello. I wanted to share that your update actually broke my website, since there are several server-level restrictions that don’t allow https calls to 3rd party resources (fonts) when the pages are delivered via http.”
——
Please read the description of the plugin: “Only install this Plugin if your web server supports https”
Sure there will be some problems if the website is accessible via http, too.
I think you missed some settings in your WordPress setup. Please read the following article: https://www.thepolyglotdeveloper.com/2014/12/force-https-pages-wordpress-site/
It’s your mistake, not mine.
Regards
Marius