does not work at all

Does not support wild cards so totally useless.

Not work.
I try to use like a block noisy web pages.
like examle.com 0.0.0.0

The extension rewrites the URL to http://«ip»/«hostname»/, and I assume some internal magic to remove the hostname from the path again and to set the correct Host: header.

The problem with this approach is that it breaks some sites; href="/foo", src="/assets/bla.css" removes the /hostname part from the URL, causing these kind of links to break.

I would be interested in a version of this that does not rewrite the URL, but I can imagine that will be hard to do within Firefox' extension API.

good stuff

Helped me when a website's DNS round robin was broken

Very useful! Congrats & thanks!
Would be nice to have the option to avoid changing the URL in the browser as some SPA rely on it.

The extension seems to just rewrite the URL to replace the domain name with an IP address before making a request. When I add a rule to point www.example.com at 127.0.0.1, and type https://www.example.com in the address bar, the browser just goes to https://127.0.0.1, instead of what I'd expect it to do which was direct the browser to connect to 127.0.0.1 but keep the Host header as www.example.com. It might be useful for people testing non-HTTPS sites without a virtual hosting configuration, but I'm not in that situation so this extension doesn't help with my needs at all.

Pop-up to add new rules is really crappy, closes all the time, does not have a way to update in bulk... and tweaking more settings is required to make it work.

Doesn't set the Host header, but otherwise it works.

This satisfies my immediate need - bypassing flaky DNS on my intranet VPN - pretty well! Enter hostname, enter IP, click "Add", click "Save".

There is still some room for improvement. Like many other reviewers I initially got tripped up by the form's habit of clearing itself, meaning that one field must be manually typed. And by the Save button, which must be clicked quite promptly or the data will disappear again. Both of these can be addressed with practice, though.

My one other issue is its URL rewriting rule - it looks fairly nice as e.g. "http://127.0.0.1/www.example.com/", but Firefox can't understand that entry format, so if you edit the URL at all (or even just hit enter on it) Firefox will no longer know what you mean and it will garble the URL.

That said, this extension is already quite helpful and it shows good potential too!

Only works if network.trr.mode is set to 0. Fails if DNS over HTTPS is enabled.