Launching the CI/CD and R Collectives and community editing features for How do I chop/slice/trim off last character in string using Javascript? XSS attacks occur when an attacker uses a web application to send malicious code, generally in the form of a browser side script, to a different end user. A simple test can first be created with this: Once the browser renders the JavaScript the pt>prompt(299792458);ipt> Shows a pop up,