Some tricks I had to do to recover a class object definition from a saved one on a running Espruino Pico

That's great - a really neat. There's a lot of data hanging around inside Espruino that dump() doesn't reconstruct properly.

So the issue is you have something like this?

function Test() {
  console.log("Hello");
}
Test.prototype.foo = function() {
  console.log("Hello 2");
};

a = new Test();
delete Test; // we've now lost the original 'Test'
dump();
// outputs just:
// var a = Object.create(a.__proto__.constructor["prototype"]);

Potentially that is something I could fix in Espruino - maybe by detecting that no top-level name has been found and by making a temporary name to use? I know dump() isn't that smart at recreating objects.

I'll make a note about this in this long-standing bug.