Guess what? Firefox 65 is here! It was just released today and we grabbed the installation and dropped in our Browserling browser cloud. It's fully ready for you and you can run your tests on it or just try the newest features and updates.

Firefox 65 Version

Try Firefox 65 in Browserling now!

What's new in Firefox 65?

  • Enhanced tracking protection: Simplified content blocking settings give users standard, strict, and custom options to control online trackers. A redesigned content blocking section in the site information panel (viewed by expanding the small "i" icon in the address bar) shows what Firefox detects and blocks on each website you visit. To learn more about content blocking, visit the Mozilla Blog.
  • A better experience for multilingual users: An updated Language section in Preferences allows users to install multiple language packs and order language preferences for Firefox and websites, without having to download locale-specific versions.
  • Support for Handoff on macOS: Continue browsing across devices. Pick up where you left off with iOS (via Firefox or Safari) on Firefox on Mac.
  • A better video streaming experience for 64-bit Windows users: Firefox now supports the next-generation, royalty-free video compression technology called AV1. Read about Mozilla's contribution to this new open standard.
  • Improved performance and web compatibility, with support for the WebP image format: WebP brings the same image quality as existing formats at smaller file sizes, which saves bandwidth and speeds up page load.
  • Enhanced security for macOS, Linux, and Android users via stronger stack smashing protection which is now enabled by default for all platforms. "Stack smashing" is a common security attack in which malicious actors corrupt or take control of a vulnerable program.
  • Firefox will now warn you when closing a window (regardless of whether you have automatic session restore enabled for restart).
  • Easier performance management: The revamped Task Manager page found at about:performance now reports memory usage for tabs and add-ons.
  • Improved the pop-up blocker to prevent multiple pop-up windows from being opened by websites at the same time.
  • Firefox for Windows is now available with 32- and 64-bit MSI installers for easier enterprise deployments.
  • Additional support for Flexbox: Launched a new Flexbox inspector tool that details Flexbox containers and helps debug Flex item sizes.
  • All CSS changes made in the Rules panel are now tracked in the new Changes tab.
  • Added support for the Storage Access API on desktop platforms.
  • Some Linux users may experience performance issues with the Downloads panel.

Developer details for Firefox 65

  • The Flexbox inspector is now enabled by default.
  • Support has been added to the JavaScript Debugger for XHR Breakpoints.
  • Right-click on an item in the accessibility tree from the Accessibility viewer to print it as json to the JSON viewer.
  • The color contrast display of the Accessibility Picker has been updated so that if a text's background is complex (e.g. a gradient or complex image), it shows a range of color contrast values.
  • The Headers tab of the Network Monitor now displays the Referrer Policy for the selected request.
  • When displaying stack traces (e.g. in console logs or the JavaScript debugger), calls to framework methods are identified and collapsed by default, making it easier to home in on your code.
  • In the same fashion as native terminals, you can now use reverse search to find entries in your JavaScript console history (F9 on Windows/Linux or Ctrl + R on macOS, then type a search term, followed by Ctrl + R/Ctrl + S to toggle through results).
  • The JavaScript console's $0 shortcut (references the currently inspected element on the page) now has autocomplete available, so for example you could type $0.te to get autocomplete suggestions for properties like $0.textContent.
  • The edits you make in the Rules view of the Inspector are now listed in the Changes panel.
  • Events are now dispatched on disabled HTML elements, i.e. <button>, <fieldset>, <input>, <select>, and <textarea> elements with disabled attributes set on them.
  • Removing the src attribute of an <iframe> element now causes about:blank to be loaded into it, giving it parity with Chrome and Safari. Previously removing src had no effect on the iframe content.
  • Support for the referrerpolicy attribute on <script> elements added.
  • Strings now have a maximum length of 2**30 - 2 (~1GB) instead of 2**28 - 1 (~256MB).
  • The globalThis property, which always refers to the top-level global object, has been implemented.
  • Readable Streams have been enabled by default.
  • The Storage Access API has been enabled by default.
  • Performance.toJSON() has been exposed to Web Workers.
  • XMLHttpRequest requests will now throw a NetworkError if the requested content type is a Blob, and the request method is not GET.
  • The WebGL BPTC and RGTC texture compression extensions have been exposed.
  • Mutation events have been disabled in shadow trees.
  • The non-standard MediaStream property currentTime has been removed.
  • The dom.webcomponents.shadowdom.enabled and dom.webcomponents.customelements.enabled prefs have been removed - Shadow DOM and Custom Elements can no longer be disabled in about:config.
  • The non-standard DOM text event - fired to notify the browser editor UI of IME composition string data and selection range - has been removed.

Other Firefox 65 Updates

  • Support for WebP images has been added. In addition, to faciliate cross-browser compatibility in certain situations the We@bP MIMEType (image/webp) has been added to the standard HTTP Request Accept header for HTML files.
  • The tabs API has been enhanced to support tab successors - a tab can have a successor assigned to it, which is the ID of the tab that will be active once it is closed. In particular: The tabs.Tab type now has a successorId property, which can be used to store/retrieve the ID of the tab's successor.
  • The headerURL/theme_frame properties for Webextension themes are now supported on Firefox for Android.

Fixed issues in Firefox 65

  • CVE-2018-18500: Use-after-free parsing HTML5 stream.
  • CVE-2018-18503: Memory corruption with Audio Buffer.
  • CVE-2018-18504: Memory corruption and out-of-bounds read of texture client buffer.
  • CVE-2018-18505: Privilege escalation through IPC channel messages.
  • CVE-2018-18506: Proxy Auto-Configuration file can define localhost access to be proxied.
  • CVE-2018-18501,18502: Memory safety bugs fixed in Firefox 65 and Firefox ESR 60.5.

Have fun cross-browser testing in Firefox 65!