Headless Browser
A headless browser is a web browser that operates without a graphical user interface (GUI). It runs on a server and can be controlled programmatically. Speed Kit uses headless Chrome to render Client-Side Rendered (CSR) pages on the server. It visits the page, executes the JavaScript to build the content, and then takes a snapshot of the final, fully-rendered HTML. This snapshot can then be cached and served instantly to users, solving the inherent performance problems of CSR.
Related web performance terms
- HAR
A HAR (HTTP Archive format) file is a JSON-formatted log of a web browser's interaction with a site. It contains a detailed, timestamped record of every single network request and response, includi…
- HTML Size
The amount of data (in bytes) that comprises the HTML document sent from the server to the browser. This includes the HTML markup but excludes CSS, JavaScript, images, and other resources.
- HTMLImageElement.prototype.src Setter
This is a sophisticated programming technique used by Speed Kit's algorithm to accurately measure the Largest Contentful Paint (LCP) on complex, JavaScript-heavy sites.
- HTTP/2
HTTP/2 is a major version of the HTTP protocol designed to make websites faster and more efficient. Its key feature is multiplexing, which allows a browser to download multiple resources (like CSS…