In order to measure the user experience, Firefox collects a wide range of anonymized timing metrics related to page load, responsiveness, startup and other aspects of browser performance. Collecting data while holding ourselves to the highest standards of privacy can be challenging. For example, because we rely on aggregated metrics, we lack the ability to pinpoint data from any particular website. But perhaps even more challenging is analyzing the data once collected and drawing actionable conclusions. In the future we’ll talk more about these challenges and how we’re addressing them, but in this post we’d like to share how some of the metrics that are fundamental to how our users experience the browser have improved throughout the year.