Describe the bug
A clear and concise description of what the bug is, including expected behavior.

• steps
  place a cauldron above a magma block, fill it with water, then, after the water boils, drop 4 mushrooms.
• expected result
  mushroom soup is crafted
• actual result
  mushrooms are not processed

Screenshots or crash report (if relevant)
If applicable, add screenshots to help explain your problem.

Versions (please complete the following information):

• Minecraft: 1.16.1 > 1.16.5**
• FORGE: 36.1.32
• Mantle: Mantle-1.16.5-1.6.109
• Inspirations: Inspirations-1.16.5-1.2.3.37

Does it work if you right click the cauldron with the mushrooms? Dropping was never the main way to craft.

So water only "boils" when fire is placed under the cauldron. Other heat sources doesn't make it boil. I don't know if this is an expected feature but in 1.12.2 it was

Just to clarify. Doing right click with the recipe items rather than throwing them directly into the cauldron only works when water actually boils. That only happens when fire is below the cauldron.

Magma blocks never made it boil in Inspirations, that was an addon/modpack. Sounds to me like you assumed it was boiling when it was not. If you saw bubble particles, this is a bug, but otherwise this is misunderstanding mechanics.

Currently supported sources of boiling are fire and campfires.

thanks for the info.

To anybody running into this conversation in the future:

I'd mistake dynamic surrounding particles which make cauldron interact with other "heat sources" but actually it was not inspirations::boiling_water :'))