This is nothing new. It is called the "Bird-Larsen Attack".
It cannot be forced, and so you must have an alternative.
1.f4 g6 stops it.
1.f4 d5 2.Nf3 g6 stops it.
Playing b3 before move 4 is just outright bad. You must establish control of d4 first. Unless of course you play 1.b3, but that is a different opening as you do not control e5, so 1.b3 e5!
1.f4 d5 2.b3? d4 advantage Black.
1.f4 d5 2.Nf3 Nf6 3.b3? d4 advantage Black.
1.f4 d5 2.Nf3 c5 3.e3 Nf6 and only now is 4.b3 OK for White.
I like playing bird's opening sometimes and thought it would be fun to make a variation on it. I'm thinking of calling it "Bird's Opening, Fianchetto variation". I have used an engine and it says it's pretty good. I would like some real people feedback.
The idea:
- Fianchettoed your bishop and develops your knight
- Get control of the 2 center black squares
- The only move that doesn't give white a big advantage is a6 after e3