Debug inserting a <script> element into my view file

The following alien element appears in my page source file after rendering by the browser. I don't know why.

<script type="text/javascript"  id="debugbar_loader" data-time="1584375481" src="http://localhost:8080/index.php?debugbar"></script><script type="text/javascript"  id="debugbar_dynamic_script"></script><style type="text/css"  id="debugbar_dynamic_style"></style>

I followed the instruction at https://forum.codeigniter.com/thread-74553.html but that only removes the inserted comments at the top and at the bottom. For me the comments have no effect, but this script element has an effect.

Please help.