Chromium Blog: Chrome 40 Beta: Powerful Offline and Lightspeed Loading with Service Workers

Chromium Blog

News and developments from the open source browser project

Chrome 40 Beta: Powerful Offline and Lightspeed Loading with Service Workers

Thursday, December 4, 2014

BetaService WorkersThis release adds service workers, a powerful new API that allows developers to make sites work offline by intercepting network requests to deliver programmatic or cached responses. Besides enabling a rich offline experience, developers can also use the API to achieve dramatic performance improvements by caching UI and other common resources between page loads.
A before and after comparison of a repeat visitor loading a site that uses Service Workers.
PushBackground SyncFetch APICache APIpolyfillHTML5 Rockscollection
Other updates in this release

This release brings support for the new directives introduced in Content Security Policy (CSP) Level 2.

The new reportValidity method causes Chrome to draw the user’s attention to form fields with validation errors, saving developers from needing to implement this feature manually in JavaScript.

Chrome now supports the minlength attribute, a validation feature that allows developers to declare a lower bound on the number of characters a user can input.

Thanks to a collaboration with Intel's Open Source Technology Center, Chrome on Mac now uses HarfBuzz for text shaping which improves performance and rendering of non-Latin text, brings new optimizations, and unifies the font system across all platforms.