Forest growth/burning bug

i stumbled on this gameplay issue in a recent boreal game. The red dragon caused huge forest fires that flowed across the map. This was problematic cause i was trying to clear forests and they would get burnt down before the worker finished. How ever if i had a worker start building something in a new forest, were you dont have to clear the forest first, and a fire came by and burnt down the forest the worker would finish his building while the fire was still going on his tile. after he finished the forest would regrow over the upgraded tile. An example of this is the mine 1 tile south of the workers currently selected.

P.S. I am playing the Vampires so its not an elf, I'm fancy so I can build in the woods, issue.

Yeap, Acheron will do that. If you want to make some Firefighters you can get adepts trained to use the Spring spell (if you have access to water mana) and have them run out to put out the fires. You may also want to consider creating fire breaks where you chop forests that would hook you up to larger forests and protect your forests from spreads (hard to do in the middle of a massive fire though).