Burning mobs won't get extinguished by rain in warm patches of Frozen Ocean biome

Bug description

• Rain in warm patches of Frozen Ocean appears to be rain, but ...

• The rain do NOT extinguish burning mobs.

How to reproduce

1. Create a Buffet world with biome 'Frozen Ocean' and allow cheats.

2. Find an area with unfrozen water (which is the warm patches of Frozen Ocean)

3. Use the command

   /weather rain 1000000

   to make rain.

4. Use the command

   /summon minecraft:armor_stand ~ ~ ~ {Fire:1000s}

   The armor stand won't stop burning and will eventually break due to fire damage. (In normal rain the armor stand will get extinguished.)

Related bugs

• MC-230678

• MC-135034

I guess the bug is caused by deciding rain/snow only according to the biome and ignoring anything else.