Rated 5 out of 5 stars

Useful, but may I suggest using decodeURI() to parse the addresses? The name of my recipients are not always in ASCII characters so a long list of URI escape sequences do not help. Something like:
// Arguments
URL = decodeURI(document.URL);
console.log(URL);
addresses = URL;

This review is for a previous version of the add-on (3.8). 

Rated 5 out of 5 stars

Works great and already prevented me a few times to write corporate emails from my Gmail address!

I'm using v2.5 on TB60.8.0, and one improvement I'd love to have, is to be able to define a *set of domains* as the "boundary" (in my case, both `mycompany.io` and `mycompany.com`).

Indeed, for the moment, I get unnecessary warnings when I write emails from my `ebosi@mycompany.io` to `bigboss@mycompany.com`, and none when I write to the latter address from `funny_nickname_lol_xd@gmail.com`.

This review is for a previous version of the add-on (3.1). 

Rated 5 out of 5 stars

Nice. It works. Thanks.

It would be nice if it would allow to add (and check) also the "@" part.

My use case: I'd like to treat "@gmail.com" as one domain, however "@lists.gmail.com" as other - warning required.

(Please note it's not literally for gmail.com, but you get the point.)

This review is for a previous version of the add-on (2.1). 

Rated 5 out of 5 stars

Nice idea. Very simple setup just one box to type it in.
I tried to use this add-on and got no warning dialog at all. I tried filling out with full emails and the @domain yet could not get this add-on to work.

Then the by Graeme Developer "Graeme" gave me a heads up. What I needed to do was put the domain only with no "@"
- gmail.com for example.

Thanks for putting your add-on "out there".

This review is for a previous version of the add-on (1.1.1). 

What you need to put in the setup is the domain - gmail.com for example - no @ no email address.
Try out CheckDomain - it has a similar idea about allows for more accounts.
Blessings
Graeme