I am aware of the new uru weapon in Avengers: Infinity War, the Stormbreaker, and how it can summon the bi-frost etc. But what's with the fire around it? Is it not supposed to have lightning/sparks around it, like Thor's fingers? Any idea or comic reference for that?
I don't think it's really a fire or flame, I see this more as blue aura.
And blue aura means something powerful and/or magical.
The Stormbreaker is very powerful, hence the blue aura is expected.