Jenkins pipeline parallel stages in separate workspaces

gistfile1.txt

pipeline {
  agent any
  stages {
    stage('first') {
      parallel {
        stage('firstA') {
          steps {
            ws('A') {
              sh '''pwd
                echo 1 > shared.txt
              '''
            }
          }
        }
        stage('firstB') {
          steps {
            ws('B') {
              sh '''pwd
                echo 2 > shared.txt
              '''
            }
          }
        }   
      }
    }
    stage('second') {
      parallel {
        stage('secondA') {
          steps {
            ws('A') {
              sh '''pwd
                cat shared.txt
              '''
            }
          }
        }
        stage('secondB') {
          steps {
            ws('B') {
              sh '''pwd
                cat shared.txt
              '''
            }
          }
        }
      }
    }
  }
}