Browser Sync with a .test domain NEVER works.

I use laravel homestead by project, so I have this:

mix.browserSync({
    proxy: "https://mysite.test",
    host: "mysite.test",
    port: 3000,
    open: "external"
});

the thing open the browser to: https://mysite.test:3001 and don't show the site, blank page.

if I manually go to just https://mysite.test it works.

first, why if I say I want port: 3000, every time that I make a new 'npm run watch' they open me a new 3002, 3003, 3004 ???

and why the site open me a blank page, I mean white https://mysite.test:3001 or https://mysite.test:3002 etc. not works???

I dealing for this thing with browser sync and homestead for years! I'm sick to not found a solution. Laravel Docs of course are pretty lame about that: https://laravel.com/docs/7.x/mix#browsersync-reloading