My last 2 XM-L2 dedomed emitters went green after a couple of weeks. Even my U3 1A. This was using gasoline. I’ve thought about trying thinner or hot dedome. I’ve seen mention of using a ‘sealer’ on the led after the dedome, but I’ve yet to find what sealer anyone is actually using. Not sure if it would help or not…might just be luck and also that I’m using gasoline. So, does anyone here use sealer, and if so, what brand and what are the benefits…if any? Thanks.