Very cool! I wish more editors would exist as web services, easily solving the cross-platformity that way.
Save the file and run it at will, just like any other local app.
The app runs in an interpreter which is a browser instead of python and a load of libraries, which is no distinction at all.
Well and I can eat the cake as well, make it some native app that has proper performance.
This is open source, so whether or not it's a web app should make no difference here
It just uses a browser as the interpreter environment and super effortless one-click instantaneous install process.