Need help with xss

Hello, I’m a budding bug hunter. By checking out one web application, let’s say https://www.example.com.
I pasted this payload into the url of the site 'alert\x2823\x29’instanceof{[Symbol.hasInstance]:eval} (the payload itself) after I changed it on this page of the resource, just a white screen to tell me what it means. For many people this may seem like a silly question but I have not found anywhere on the Internet what it means. The payload was taken from the Gitkhab. https://github.com/RenwaX23/XSS-Payloads/blob/master/Without-Parentheses.md And I got it right that she’s bypassing the Waf. Thank you in advance, and I’m sorry if I misspelled it.

Hi!

May you upload a screenshot and source-code? So we can help you better.