The "key" parameter passed to replacer is of number type for array elements

[james-hu]

Try this code with both JSON.stringify and safe-stable-stringify:

const keys: Array<any> = [];
JSON.stringify(['a', 'b'], function (key: any, value: any) {
  keys.push(key);
  return value;
});
console.log(jsonStringifyKeys);

And then you will find that JSON.stringify passes strings "0" and "1" to the replacer function, while safe-stable-stringify passes numbers 0 and 1.

[BridgeAR]

Thanks for the report @james-hu! This is fixed in 2.4.3.