Not a particularly hard task, but converting all tests is a lot of work. We want to go from:

# Promisify
is ref Mojo::Promise->resolve('foo'), 'Mojo::Promise', 'right class';
$promise = Mojo::Promise->reject('foo');
is ref $promise, 'Mojo::Promise', 'right class';
@errors = ();
$promise->catch(sub { push @errors, @_ })->wait;
is_deeply \@errors, ['foo'], 'promise rejected';
$promi

• Filestack
• Google-Ads-Overview Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2272.118 Safari/537.36
• Google-Ads-Overview Mozilla/5.0 (Linux; U; Android 6.0.1; generic) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2272.118 Version/4.0 Mobile Safari/537.36
• Google-Ads-Overview Mozilla/5.0 (Linux; U; Android 2.3.4; generic) AppleW

An outage in myip.ms caused one of the lists to fail downloading - which caused error in testing, and was not recoverable.
Think of creating backup files for recovery from list providers outages

Small observation:
When choosing an user agent, it requires selecting the user agent, followed by clicking "Apply".
When resetting the user agent (using the system's user agent), pushing "Reset" will apply it automatically.

It would be more consistent to always require "Apply" in order to apply any user agent changes.