Why is the explosion from 'Armour explosion' not detonating the gas clouds from 'Gas Arrow'?

Hello, Ranger here.
I noticed that the explosion from the 'Armour explosion' is not detonating the gas clouds from the 'Gas Arrow'. Is this a bug? The 'Armour explosion' has 'Fire' and 'Explosion' and should detonate the gas clouds or do I misunderstand something?

Fire and Explosion do not mean "detonate".

To detonate the gas, you need a burning mob to touch the could OR use a "detonator" skill, such as some of the crossbow skills or 1 of the bow arrows (forgot the name).

i bet its the classic "trigger cannot trigger"

flame wall works(?)

I figured that "flame wall" and the detonator arrow works. I am frustrated that a fire explosion is not working to explode the gas. Either a bug or poor early game design...