.js

const manager = {
  counter: 1,
  user: null,
  pass: null,
  
  receiveCreds(user, pass) {
    manager.user = user;
    manager.pass = pass;
    
    // increment counter
    manager.counter += 1;
    
    // store a SNAPSHOT of the counter, which
    // can be used inside the closures
    const counter = manager.counter;

    setTimeout(() => {
      if (cred.counter !== counter) {
        // receiveCreds has been called again,
        // which caused the counter to increment
        return;
      }
      
      clearCredentials();
    }, ONE_HOUR);
  }
}