“ However, what scared me last time was I was trying to snuff out the flame ”

One way is to drop an aluminum cupcake foil over the stove to snuff it.
Another way is to let it burn out. This comes with experience on how much fuel to use.
There’s a stove by Zelph that won’t let the fuel spill if it tips over.

“do any of you have experience with these caps …”

Glenn said it best. It’s easy to crispy up those rubber rings. Check the trangia directions.

Any stove is dangerous. Just practice well in a safe place before taking it in the wilderness.

Happy cooking,
-Barry
-The mountains were made for Tevas