> As a full-time firefox user, I commonly find that sites have bugs, and when I boot it up in Chrome just to check my hunch, they don't manifest.

You can report sites broken in Firefox (or other browsers) at https://webcompat.com/. Mozilla web developers will debug the broken site and either file a Firefox bug report or try to reach out to the site developer.

Mozilla even has a convenient Firefox extension to make reporting broken sites quick and easy:

https://addons.mozilla.org/en-US/firefox/addon/webcompatcom-...