Firefox 87 rolls out with Smart Block and improved referrer trimming
Firefox has received a new update bumping it up to version 87. After receiving an update back in February, the new version brings two important features: Smart Block and improved referrer trimming.
Firefox blocks third-party tracking scripts by default, and while it works pretty well, there are certain cases where a script is not tracked. This can lead to an interference with a page’s rendering where it is either delayed or completely breaks. With Smart Block, Firefox adds an extra step where pages that embed third-party trackers are rendered properly. “SmartBlock intelligently fixes up web pages that are broken by our tracking protections, without compromising user privacy,” says Mozilla in its security blog.
By providing local stand-ins bundled with Firefox, the browser provides scripts that behave just like the original ones to ensure that the website works properly. This helps break sites that rely on the original scripts to load without compromising on their functionality. As additional security, no third-party content from the trackers is loaded, so chances of tracking you are not possible. Firefox has also made sure that these stand-ins do not contain any code that would support tracking functionality.
The new Firefox 87 update also adds strict rules when it comes to HTTP referrer headers. Traditionally, browsers send the full URL of the referring document (typically the URL in the address bar) in the HTTP Referrer header with virtually every navigation or subresource (image, style, script) request. This information can be used for various things, including analytics, logging, or for optimizing caching. The HTTP Referrer header often contains private user data, for instance, what article a user is reading on the referring website, or even includes the user’s account information on a website. The latest update will set the default Referrer-Policy to ‘strict-origin-when-cross-origin’ that will trim user-sensitive information accessible in the URL. It will trim information for requests going from HTTPS to HTTP and trim path and query information for all cross-origin requests.
The new Firefox 87 update will also offer improvements to the Highlight All feature of Find in Page, where tick marks will be displayed alongside your scrollbar that corresponds to the location of matches found on that page. There will also be full support for macOS’ built-in screen reader VoiceOver and various other minor UI enhancements, along with security and general tweaks.