title: Codeigniter: URI you submitted has disallowed characters
body: <p>My URL is:</p>
  
  <pre><code>https://example.com/c3dlZXRfcmFqdmk5MUBob3RtYWlsLmNvbQ=
  </code></pre>
  
  <p>When I remove <code>=</code> then it works fine.</p>
  
  <p>I have this in <code>config.php</code></p>
  
  <pre><code>$config['permitted_uri_chars'] = 'a-z 0-9~%.:_\-';
  </code></pre>
  
  <p>Error:</p>
  
  <pre><code>The URI you submitted has disallowed characters.
  </code></pre>
  
  <p>How can I allow <code>=</code> or <code>==</code> signs in URI?</p>
  
  <p>I have tried it by changing this:</p>
  
  <pre><code>$config['permitted_uri_chars'] = 'a-z 0-9~%.:_\-='; // added = sign at the end
  </code></pre>