How to get active user email with installed onEdit trigger?

user_email_onEdit.gs

function onOpen() {
  var ui = SpreadsheetApp.getUi();
  ui.createMenu('😎📬 run me 2x times')
      .addItem('please let script to see your email', 'install')
      .addToUi();
}


// function test() {
//   var e = {
//     range: SpreadsheetApp.getActive().getSheetByName('test_onEdit').getRange('B2')
//   }
//   edit_(e)
// }
function edit_(e) {
  var targetcol = 1;
  if (e.range.getSheet().getName() === 'Sheet1') {
    var user = Session.getActiveUser().getEmail();
    if (user !== '') {
      var col = e.range.getColumn();
      var rows = e.range.getHeight();
      var ratgetrange = e.range.offset(
        0,
        targetcol - col,
        rows,
        1);
      ratgetrange.setValue(user);
    }
  } 
}

function install() {
  setOnEditTrigger_(
    SpreadsheetApp.getActive().getId(),
    'edit_');
}


/**
 * create onEdit trigger
 * 
 * @param {string} spreadsheetId
 * @param {string} functionName
 * 
 */
function setOnEditTrigger_(spreadsheetId, functionName) {
  console.log('OnEdit trigger ' + functionName +
     ' for new file' +
     spreadsheetId);
  var trigger;

  if (existsOnEditTrigger_(functionName, spreadsheetId)) {
    console.log('stopped execution. Trigger exists.');
    return;
  }

  trigger = ScriptApp
    .newTrigger(functionName)
    .forSpreadsheet(spreadsheetId)
    .onEdit()
    .create();  
  
  console.log('Created new trigger!')
  return trigger.getUniqueId();
}

/**
 * check if onEdit trigger exists
 * 
 * @param {string} spreadsheetId
 * @param {string} functionName
 * 
 */
function existsOnEditTrigger_(functionName, spreadsheetId) {
  var triggers = ScriptApp.getProjectTriggers();
  var trigger = {};  
  for (var i = 0; i < triggers.length; i++) {
    trigger = triggers[i];
    if (
      trigger.getHandlerFunction() === functionName && 
      trigger.getTriggerSourceId() === spreadsheetId &&
      trigger.getEventType().toString() === 'ON_EDIT') return true;
  }  
  return false;
}