You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query>
    <random>
      <page id="258" ns="0" title="Citrix® x86 64-Client Version 13.10 auf Ubuntu Linux 18.04 installieren (4.15.0-36-generic)" />
      <page id="250" ns="0" title="TM1637 LED Display ansteuern - Only 4 PIN Red Common Anode 4-Segment Digital Tube Display For Arduino Raspberry" />
    </random>
  </query>
</api>