Microsoft is phasing out JScript in Windows 11 24H2 in favor of JScript9Legacy to enhance security. JScript9Legacy is enabled by default and will manage all scripting processes previously reliant on JScript without requiring user action. This new scripting engine offers improved performance, compatibility with modern web standards, and advanced security features to mitigate risks such as cross-site scripting (XSS). The transition is designed to be seamless, although Microsoft has not provided procedures for reverting to JScript if compatibility issues arise. The change is limited to Windows 11 24H2, with no updates planned for earlier Windows versions.