Hobbyist here
Seems obvious reading the listings and datasheets after the fact, but not digging into the details I didn't think much about the term flame retardant before placing some orders. Flame retardant meaning they won't sustain a flame once heat (power) is REMOVED.
Having dealt with self-extinguishing 3d print plastics normally this is well good enough, overkill even, but given a resistor is the heat source, it will sustain a flame while overloaded.
My very non-scientific tests to assess the short-circuit behavior of two resistors I got. A flame proof Yageo part, and a flame retardant coated stackpole part. Suffice it to say, don't want to let it get this far in-circuit. This is way beyond the rated spec obviously:
https://photos.app.goo.gl/aeMLaQYQAbZmiqmi9