Some Web browsers convert these characters into hexadecimal codes when the URL is copied, but others do not. (E.g. some versions of Chrome for Android don't do it.) This can result in a situation where you cannot conveniently copy the browser's current URL and paste it into a chat for somebody else to click on, unless you have access to a Javascript console or similar that will let you type the command to re-code the characters (which is especially awkward on a mobile device).

As a convenience, I have therefore posted the form below which simply calls your browser's encodeURI on any text you paste in. Place the link in the first box, and copy the resulting version out of the second box to paste into the chat. You can read this page's source to confirm it's not sending your link to any other server. This explanation is hidden by default so that it doesn't get in the way when you use this tool on a mobile device.