title: How to add headers to a browser request without any browser extensions?
body: <p>Sometimes, one needs to add special headers to each request or specific requests made from a browser. The common approach to do this is by using browser extensions which allow us to modify request headers. Is there another way to do this, without any browser extension ?</p>
  
  <p>PS - I have searched SO and not found a single post which actually suggests or shows how to do what I need.</p>