Melllvar

Reminds me of the old trick on HTML forms where you use CSS to make one of the form fields invisible to humans and reject any submission that filled in that field.

Looks like compatibility hacks for various websites.

Interventions - are deeper modifications to make sites compatible. Firefox may modify certain code used on these sites to enforce compatibility. Each compatibility modification links to the bug on Bugzilla@Mozilla; click on the link to look up information about the underlying issue.

User Agent Override - change the user agent of Firefox when connections to certain sites are made.

https://wiki.mozilla.org/Compatibility/UA_Override_&_Interventions_Testing

The value of the DNS is that we all use the same one. You can declare independence, but you’d lose out on that value.