public/index.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8" />
    <link rel="icon" href="%PUBLIC_URL%/favicon.ico" />
    <meta name="viewport" content="width=device-width, initial-scale=1" />
    <meta name="theme-color" content="#000000" />
    <meta
      name="description"
      content="Web site created using create-react-app"
    />
    <link rel="apple-touch-icon" href="%PUBLIC_URL%/logo192.png" />
    <!--
      manifest.json provides metadata used when your web app is installed on a
      user's mobile device or desktop. See https://developers.google.com/web/fundamentals/web-app-manifest/
    -->
    <link rel="manifest" href="%PUBLIC_URL%/manifest.json" />
    <!--
      Notice the use of %PUBLIC_URL% in the tags above.
      It will be replaced with the URL of the `public` folder during the build.
      Only files inside the `public` folder can be referenced from the HTML.

      Unlike "/favicon.ico" or "favicon.ico", "%PUBLIC_URL%/favicon.ico" will
      work correctly both with client-side routing and a non-root public URL.
      Learn how to configure a non-root public URL by running `npm run build`.
    -->
    <title>React App</title>
    <script src="https://code.jquery.com/jquery-2.2.4.min.js" integrity="sha256-BbhdlvQf/xTY9gja0Dq3HiwQF8LaCRTXxZKRutelT44=" crossorigin="anonymous"></script>
  </head>
  <body>
    <h1>SPA</h1>
    <div><button id="launch-button">Launch JQL</button></div>
    <noscript>You need to enable JavaScript to run this app.</noscript>
    <div id="jira-issueml-single"></div>
  </body>
  <script>
  $("#launch-button").on('click', () => {
    console.debug('launch-button click');
    $("#jira-issueml-single").css('display', 'block');
    if (!window.renderedApp) {
      window.renderApp(document.getElementById('jira-issueml-single'));
      window.renderAppUnload = _ => {
        $("#jira-issueml-single").css('display', 'none');
      };
    }
    window.renderedApp.searchJiraIssues();
  });
  </script>
</html>