This documentation is not using the current rendering mechanism and will be deleted by December 31st, 2020. The extension maintainer should switch to the new system. Details on how to use the rendering mechanism can be found here.
As explained in the introduction, this extension allows you to do redirects via TypoScript, so all configuration is done in TypoScript.
When called, the script will compare current URL with all his parameters to the target, if target is different then it's redirect to this page, this prevent a direct infinite loop.
You should always be careful not to create an infinite redirection between two pages that redirect one to the other..