I was in Ranked Practice (17 oct 2020) playing through the web site (unity) interface.
I was ARSONIST.
I tried to douse a vigilante who was jailed.
The text message said that my ability failed because the target was in jail. (This is correct.)
HOWEVER the orange gasoline can icon that appears next to the people doused, appeared next to his name.
I ignited later in the game. He did not burn. Therefore the text message and functionality was correct. He was not doused, because he was in jail. But the orange gasoline icon next to his name, in the "ALL LIVE TOWNIES" box, remained next to his name.