The "#comment" at the end of the URL. It's a title/heading/fragment in HTML that hints to your browser to go there directly.

Like this: https://en.wikipedia.org/wiki/URL#fragment

Everything after the # character in the URL is called an anchor and it's not actually being sent to the website server so it's meant for your browser (though the server can see it using javascript). The anchor can point to any ID in the HTML of the web page and browser will scroll it into view on page load. You can find the ID of any element using right click -> inspect though not all elements have explicit ids.

I've no idea to be honest.