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    <p>With at least the two most recent kernel versions</p>
    <p><span style="font-family:monospace"><span
          style="color:#000000;background-color:#ffffff;">linux-image-5.13.0-25-generic<br>
        </span></span><span style="font-family:monospace"><span
          style="color:#000000;background-color:#ffffff;">linux-image-5.13.0-27-generic</span><br>
      </span></p>
    <p>ubuntu switched to ZSTD as default kernel compression method
      breaking all Xen installations using "pygrub", regardless whether
      it's a Dom0 or a DomU.</p>
    <p>Please switch back to a "pygrub" supported kernel compression
      method.</p>
    <p>Best, Oliver<br>
      <span style="font-family:monospace"><span
          style="color:#000000;background-color:#ffffff;"></span></span></p>
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