Does it contain Firefox? How about Chrome?

Quote from LittleSnitch:

> Little Snitch for Linux is built for privacy, not security

What's your definion of malware in this context?

It contains Firefox and Chromium. You are right that they may call home, but at least it's very limited and easily configurable. Could be too much for you but fine with me. Also Debian does change their config by default to minimize privacy issues: https://news.ycombinator.com/item?id=32582260

It's far from easy in the case of Firefox [0], and the last time I tried, some .mozilla.com domains would still get pinged. Chromium doesn't even have an official guide. The only options I found to be reliable are source-level patches, i.e. ungoogled-chromium and LibreWolf.

Note that LibreWolf still leaves some of the stuff on for you to manually disable (dom.push.connection.enabled, extension updates).

[0] https://support.mozilla.org/en-US/kb/how-stop-firefox-making...

In firefox, goto about:config and search for url.

You're welcome.