Chrome 43 beta brings Web MIDI support, Permissions API, and upgrading legacy sites to HTTPS

Two days after releasing the stable version of Chrome 42, Google released Chrome 43 beta for Windows, Mac, Linux, and Android. The company detailed the new features, including Web MIDI support, the new Permissions API and changes to existing APIs, and help with upgrading legacy sites to HTTPS.

Chrome is arguably more than a browser: With hundreds of millions of users, it’s a major platform that Web developers have to consider. In fact, with regular additions and changes, developers have to keep up to ensure they are taking advantage of everything available. Chrome 43 includes many new features worth outlining, especially if you’re a developer.

First up, Chrome 43 has gained support for MIDI hardware. This means you can create music without installing any specialized software, as the new Web MIDI API allows websites to communicate with connected MIDI devices (such as a USB-MIDI instrument plugged into your computer, tablet, or phone).

MIDI stands for Musical Instrument Digital Interface, a technical standard that describes a protocol, digital interface, and connectors. It lets various electronic musical instruments and related devices connect to, and communicate with, computers.

Next up is the new Permissions API, which lets developers query and observe changes to their permission status for Geolocation, Push, Notifications, and Web MIDI. Asking for permission in context means fewer unnecessary and untimely prompts for the user.

Before the Permissions API, websites could not determine the permission state of APIs. Sites would thus attempt to use APIs immediately after page load without pre-existing permission, causing users to see confusing permission prompts without an explanation.

A new CSP directive, “upgrade-insecure-resources,” causes Chrome to upgrade insecure resource requests to HTTPS before fetching them. Transitioning large collections of unmodifiable legacy content to HTTPS connections can trigger mixed content warnings because of links to insecure resources. This change should help with this as developers can serve their hard-to-update legacy content via HTTPS more easily.

Other developer additions include:

• Attributes defined on DOM objects have been moved to the prototype chain, as specified by Web IDL. This lets developers efficiently override or create methods on DOM Objects and improves compatibility with Firefox and Internet Explorer.
• The Cache Storage API, previously only available in service workers, now provides developers full imperative control over their caching in the page context.
• The autocapitalize property is now supported on input and textarea elements, allowing sites to suggest default capitalization for text typed with on-screen keyboards.
• Developers can now programmatically trigger copy and cut actions using document.execCommand(‘copy’) and document.execCommand(‘cut’) in response to a user gesture, eliminating the need to use Flash-based workarounds.
• The Fetch API now allows developers to directly operate on and incrementally release the bytes of streamed network responses, in contrast to the equivalent XMLHttpRequest functionality that requires developers keep the entire in-progress stream response in memory.
• showModalDialog was disabled by default in Chrome 37, and in accordance with the public deprecation timeline, this release removes the Enterprise Policy setting created to temporarily re-enable it.
• Chrome OS now fires devicemotion events on pages at a regular interval, allowing developers to track the device’s acceleration in the same way they do on Chrome for Android, Windows, Mac, and Linux.
• The Web Audio API now allows developers to selectively disconnect specific connections to an AudioNode or AudioParam, avoiding the audio artifacts caused by disconnecting all inputs and then manually re-connecting those that should have been retained.
• Developers using the Web Audio API can now also explicitly close an AudioContext, releasing all allocated system audio resources instead of depending on unpredictable garbage collection.

Google releases new versions of Chrome every six weeks or so. We thus expect Chrome 43 (stable) to arrive by the end of May.