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HTML is good for debugging, but probably is not suitable for your application.
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<?xml version="1.0"?>
<api>
  <query>
    <allmessages>
      <message name="ipb-blocklist" xml:space="preserve">View existing blocks</message>
      <message name="ipb-blocklist-contribs" xml:space="preserve">Contributions for $1</message>
      <message name="ipb-change-block" xml:space="preserve">Re-block the user with these settings</message>
      <message name="ipb-edit-dropdown" xml:space="preserve">Edit block reasons</message>
      <message name="ipb-needreblock" xml:space="preserve">== Already blocked ==
$1 is already blocked.
Do you want to change the settings?</message>
      <message name="ipb-otherblocks-header" xml:space="preserve">Other {{PLURAL:$1|block|blocks}}</message>
      <message name="ipb-unblock" xml:space="preserve">Unblock a username or IP address</message>
      <message name="ipb-unblock-addr" xml:space="preserve">Unblock $1</message>
    </allmessages>
  </query>
</api>