It might be possible to generate recipes dynamically to achieve compatibility with other mods: iterate through all recipes, and if plastic is detected as an ingredient, generate a corresponding molten recipe for it.
For local language files, molten-plastic-name can be used for dynamic matching.

If you don’t adopt this suggestion, I will fork your mod in the future.

Hello there,

this is currently planned and will be implemented as an optional setting.
If you decide to fork this mod please credit Malcolmriley for the fluid icon.

Thank you for your suggestion and your interest in my mod!