<!DOCTYPE html>
<html>
<head>
    <meta http-equiv="Content-Security-Policy" content="img-src https://*;">
    <script>
      async function timeout (cmd) {
        const timer = new Promise((resolve, reject) => {
          const id = setTimeout(() => {
            clearTimeout(id)
            reject(new Error('Promise timed out!'))
          }, 750)
        })
        return Promise.race([cmd, timer])
      }

      let ourOpener = window.opener;

      if (location.search.includes("close")) {
        window.close();
      }

      document.addEventListener('DOMContentLoaded', async () => {
        const frame = document.createElementNS('http://www.w3.org/1999/xhtml', 'frame');
        const image = document.createElementNS('http://www.w3.org/2000/svg', 'image');
        document.documentElement.appendChild(frame)
        image.setAttribute('href', 'a.png')
        for (let i = 0; i < 5; ++i) {
          try { await timeout(image.decode()) } catch (e) {}
        }
        let w = window.open();
        // Need to run SpecialPowers in the newly opened window to avoid
        // .wrap throwing because of dead objects.
        let csp = w.eval("SpecialPowers.wrap(document).cspJSON;");
        ourOpener.postMessage(csp, "*");
        w.close();

        if (!location.search.includes("close")) {
          window.close();
        }
      })
    </script>
</head>
</html>
