title: Send notification to specific user firebase in flutter
body: <p>How do I send a notification to another user when one user presses a button? Can someone show me a code snippet?</p>
  <p>I realize that this question was asked before, however, it was closed since there were &quot;several answers.&quot; The links that were provided that were similar did not explain sending notifications in <strong>flutter</strong>.</p>