This has gotten some attention, especially about a week ago, but I really hope more people will continue to try it and, if interested, support it. It is Firefox, but heavily modified to please a different audience that prefers a slightly different UI than Firefox. It has some of the appeal of Arc, Vivaldi, and the Sidebery extension.
In my view, it is very promising, and all competition in this space is good. Here it is on Github, also.
Can you use FF extensions with it? The web site doesn’t say one way or the other.
yes. it’s Firefox with some extra UI modifications, but it’s the same thing under the hood.