Feature request: implement sigsuspend

Hello emscripten developers,

I am on my way to port some code to the web for a client-side application. My application is using Cap'n Proto serialization from C++: https://capnproto.org/

My code is almost fully compiling under emscripten except for the lack of `sigsuspend` implementation.

I am aware of this: https://github.com/emscripten-core/emscripten/issues/12283

Any chances it will be implemented?

Alternatively, any hints on how to implement it? I am not very knowledgeable of the inner workings of the web platform itself.