Assign return value of Promise to 2 objects (Object and copy of objects)

Question

I read a .json file, parsed it to an js-Object, and set it to an object. But now I want to have two objects. One object remains as it is, and another object can be edited. After editing, I compare these two objects, and in this way, I get all the user changes. OK, now my code:

function Initialization(sPath) {
  _LoadFromFile(sPath).then((oJsObject) => {
     oObject, oObjectEdit = oJsObject;
  }).catch((err) => {
    switch(err) {
       case 'Cannot open file':
          _LoadToFile(sPath).then(() => {
          Initialization(...arguments);
          }).catch((err) => {
        console.log('Err');
          });
        break;
       default:
    console.log('Err');
        }
  });

 function _LoadFromFile(sPath) {
  return new Promise((resolve, reject) => {
    const fileName = sPath.replace(/\n|\r/g, "");
    FileSystem.ReadFile(fileName, 'utf8').then(
      function(ReadFileResolve) {
        resolve(JSON.parse(ReadFileResolve));
        }
      ).catch(function(err) {
    console.log('Err');
        reject(err);
      });
  });

So in witch way I have to set oJsObject to oObject & oObjectEdit? Do I really have to do a copy of oObject ???

oObject = oJsObject;
oObjectEdit = JSON.parse(JSON.stringify(oObject))

Thanks for your support.