If an arrow lands with ticks remaining on Fire it will burn until;
life reaches 1200 and is despawned
picked up
covered by powder snow
touched by water (any level)
/rotate @s 0 0
/summon minecraft:arrow ~2 ~10 ~4 {Fire:20s}
/summon minecraft:arrow ~-2 ~10 ~4 {Fire:30s}
Right arrow will burn for 1200 ticks, where left arrow is extinguished just before hitting the block.
Expected behavior would be that right arrow would stop burning after 0.5 seconds.
Related tickets;
Can confirm.