The data-test highlighter is a free Chrome extension designed specifically for quality assurance (QA) engineers. This tool enhances UI testing workflows by allowing users to find and highlight elements on a web page based on specified attribute names and optional values. By streamlining the process of inspecting `data-test` markers, it significantly reduces the time spent searching for elements in DevTools and facilitates quicker selector validation during both manual checks and automated test debugging.

One of the standout features of this extension is its support for live mode, which utilizes `MutationObserver` to automatically highlight new matching elements added to the DOM. Users can easily navigate through highlighted elements using built-in focus controls, making it a practical solution for efficiently managing UI testing tasks. Overall, the data-test highlighter serves as a valuable tool for enhancing productivity in the QA process.