It looks like it does, but unfortunately it doesn't.

Liftoff has "Use in app browser", but all it changes is whether the link is opened in a full Chrome window, or a "Running in Chrome" window.

It doesn't let you pick which browser you want to use.

I use Chrome for serious things (e-commerce, work, etc) and Firefox for everything else.

It gives an extra layer of protection if a vulnerability is able to steal cross site login details.