X-Clacks-Overhead Detector is a free Chrome add-on designed to detect the X-Clacks-Overhead header, displaying its value as a toast notification. This tool pays tribute to the deceased, inspired by the Clacks system from Terry Pratchett's Discworld series. By utilizing the "x-clacks-overhead" header, it ensures that the names of those who have passed away are kept alive in the digital realm.

The add-on serves as a reminder of the importance of memory and legacy in the online world. Users can easily install this simple yet meaningful tool to receive notifications whenever the header is detected, thus celebrating the lives of individuals in a unique way. It blends functionality with a touch of literary homage, making it a notable addition for fans of Pratchett's work and those interested in digital memorials.