Is your feature request related to a problem? Please describe.
N/A

Describe the solution you'd like
It would be cool if spiritfire had its own block where it will never extinguish. Also, using spiritfire and netherrack together is not visually appealing.

Additional context
A few mods, including vanilla, have this feature. For example, soul fire from vanilla can only be created on soul soil or soul sand; and soul fire or cryptic fire from Oh The Biomes You'll Go can be created on brimstone or cryptic stone, respectively.

think you can do this with a log under it
any log should work at least in the past

That is correct, I am closing this issue.
If the fire on the log does not work as expected, please create a new issue