I didn’t want to leave you hanging on this question. It currently does not seem possible.
For a replacement, you can only support desktop (Android has no support), you can set up the environment and build an executable, then distribute that executable from a website. Then after the user downloads that, they have to place it along with a special json file you give them in a special directory. Then they can install your addon, and then you can use native messaging.
Will this approach work for you?
I am trying this approach, am having a difficult time setting up the environment, am learning compiling C++ at same time, OS X is a VM for me, so Im having a tough time getting XCode on there.
I am (currently experimentally) using native messaging in an extension too.
What I do is pack a node js application with the nexe module. That way, one can write the native application completely in JavaScript too, and is still able to distribute a single binary.
It took me quite a bit of time to get this working, so if ether of you is interested in this, just ask and I will share my experience with it.
Oh wow that is extremely interesting. I had a need to create a new window and inlay a canvas, then create a canvas editor in javascript. Can that be done, cross platform, with node.js nexe?