I am looking for a way to log in into websites in Thunderbird; some feeds require a login to be able to read the posts, ie. some subreddits, Facebook, etc; but when the browser inside TB prompts for a login, and typing the login in it, it launches whatever browser is as defaut instead of login in the site.
I tried QuiteRss, Liferea, and these can login into sites and show me the feeds.
I think an option is to go into your preferences in your system, and look for something like “Preferred Applications” and go set Thunderbird for web. Try to log in then, and then reset the web back to what you had it as before.