Microsoft Edge team uses data on browser APIs and telemetry on API usage across the web for their internal planning. Today, Microsoft announced that they are releasing this data to the general public so that implementers, spec authors, and web developers all over the world can make use of it. Global CSS Property Usage is one of the new tools on Microsoft’s recently-introduced Platform Data page. This CSS usage data comes from a Bing-powered scan of 1,218,301 pages. This process detects correctly-formatted CSS properties for the browsers included in the scan. The scans run once per quarter, and the latest data set is from March 13th, 2016.
To gain better insight into the usage of CSS properties across the web, we use two crawlers: The first, powered by Bing and running the EdgeHTML engine, allow us to see the web as Edge sees it. The second, our new Azure-based Interop Crawler, allows us to see huge portions of the public internet through the eyes of any browser. This is more efficient and accurate than having to instrument our browser with no-op APIs that we don’t support just to see their relative usage across the web.
This data is incredibly valuable to the Edge team in planning since we can measure the real-world usage of any given property. For example, when comparing features or bugs, we have to determine a relative priority to determine which one gets addressed first. There are multiple inputs we take into account when deciding these, but one very important one is web usage. If one feature will enrich five sites, and another, five thousand, it makes more sense to implement the one that will address the larger set of sites.
Read about in detail here.