Those work we moves away from gas or liquid fuel over a decade ago for small stove heaters and went with a ricket stove design.
https://www.solostove.com/solo-stove-titan/
Even I rocky alpine area you can find grass to burn….
In real pinch with the vasiline cottonnballs or a wax and lint starter you can heat up food or water.
Note you will need to twist grasses into a knot so it burns intense enough.