In Helium 11 we could use 3rd party placing a DLL into .../Helium/Plugins folder.
This can be a not much used feature but it's quite powerful, since we can improve Helium experience a lot using 3rd party plugins like equalizers, spectrum analyzers, effects and other DSP plugins.
I would like to see this feature back in HMM12.
In fact, an even better implementation of this would be something like a Chain Tool, where we could load a number of DSP plugins in a chain in a specific order.
This is something that we need to test more before it can be implemented. Chaining is unfortunately not possible when using external plug-ins.