Flarum Google Fonts BBCode
Use most any Google Font thanks to Page CDN's "Easy Fonts" stylesheet.
Disclaimer: This is a fun extension and may be useful depending on the type of community. But, if you really want to get serious and you have a powerful enough server, I'm thinking the best Google Fonts BBCode would be one where you pick just 2 or 3 options for your members. Then, self host just those 2 or 3 fonts. You can fork this extension so that you see how the extend file is set up. From there, modify and link to your self hosted style sheets/font files.
Reference (to get class names needed for BBCode): https://pagecdn.com/lib/easyfonts
The BBCode starts simply with f for font.
To use, after the opening tag's equals sign, enter the appropriate class name found on the reference page (link above), but leave off the beginning "font-." To save a little bit of typing time, the beginning "font-" part of the class name is added for you.
[f=beth-ellen]This will be a handwritten cursive font called Beth Ellen.[/f]
The class in the above example will be font-beth-ellen.
Install & Update
composer require zerosonesfun/flarum-google-fonts
php flarum cache:clear
composer remove zerosonesfun/flarum-google-fonts
Optional: Self host the font(s)
FYI: If you’d like to fork this and create a version of this extension that self hosts a font, I have had success with this tool:
With this tool you may quickly select and download the font files. Then add the appropriate code to your custom CSS. Once you are hosting the font files and are calling them out in your CSS, all that is left is to make a custom BBCode. The goal is to ensure a unique CSS class is called out in a HTML span tag if a user uses the custom BBCode you specify. See this extension’s extend.php file and tweak it.
I think this will make some sense if you know how BBCode in Flarum works and know HTML/CSS basics. Otherwise, it’ll be a little tricky. Sorry. But, that’s all I have time to explain right now.