When attempting to log in, Hangish shows

Login Failed Wrong username/password

However, it is not incorrect, and running Hangish from the terminal shows the page fetched from Google instead says

The browser that you're using doesn't support JavaScript, or has JavaScript turned off. To keep your Google Account secure, try signing in on a browser that has JavaScript turned on.

Note that I have 2FA turned on, and for Hangups I had to follow the --manual-login approach. Over in #44 (comment), it was mentioned that

In the meantime, if you want to continue using hangish, I suggest you to get an authentication cookie with your computer, and create the authentication cookie for hangish yourself.

Unfortunately I cannot figure out how; searching my home directory for Hangish config files only shows local/share/harbour-hangish which contains nothing but a single empty folder also named harbour-hangish.