will not trigger an additional query. I think that the way Rails is behaving, it's because the query isn't loading in IRB. If you type p2 in the terminal again, I think it will trigger another query.
I think any of them would be sufficient and you can set the CSS to apply the font to the <body>. You'd have a CSS class for each font and that would be set based on their settings or the default font.
Are you using webpacker with this app or esbuild (or similar)? For now, you could try to take the stimulus controller from the code repo and add it into your app. Alternatively, and perhaps my current preferred approach is to use Turbo and a turbo_frame_tag with the src attribute. No javascript needed with this approach.