The official release date of Firefox 53.0 is April 19th, 2017. Mozilla will release Firefox 53 on that day on its website, and through Firefox's automatic update system.
The new Firefox 53.0 release is important for a number of reasons. First, because it does not support a number of operating systems anymore. Second, because of the dropping of Firefox Aurora from the release cycle. You find details about these changes below.
Only Firefox Stable and Beta systems are updated on this release day. Firefox Stable is updated to 53, and Firefox Beta to 54. Aurora is not updated and removed soon, and Nightly is not updated to stay on version 55 to fill the gap that the removal of Aurora left. Firefox ESR 52.1 and 45.9 are also available.
- Windows XP, Windows Vista, 32-bit Mac OS X, and Linux support for processors older than Pentium 4 or AMD Opteron, are no longer supported.
- Windows XP and Vista users on Firefox 52.x will receive security updates for another year, but no feature updates anymore.
- Firefox Aurora is removed from the release cycle.
- Firefox ships with two new compact themes (dark and light).
- Compositor process enabled on qualifying Windows systems.
- New legacy add-ons are no longer accepted on AMO.
Firefox 53.0 download and update
Firefox is configured to check for and download updates automatically. You can run manual checks for updates with a tap on the Alt-key on your keyboard, and the selection of Help > About Firefox from the menu bar.
The About Mozilla Firefox window checks for updates, and either downloads and installs any update it finds automatically, or on user request.
Direct download links for Firefox installation files:
- Firefox Stable download
- Firefox Beta download
- Nightly download
- Firefox ESR download
- Firefox unbranded builds information
Firefox 53.0 Changes
Firefox Aurora is out
We talked about the end of Firefox Aurora already here on Ghacks. Mozilla decided to remove the Aurora channel from the release cycle. The organization plans to migrate existing Aurora users to Beta eventually, and move features from Nightly to Beta directly in the future.
A special Developer Edition will be made available, based on Beta but with the same tweaks that the current Developer Edition ships with.
You can read more about the change by following the link above, or by visiting the FAQ page on the Mozilla website.
End of support for several operating systems
Firefox 53 won't support the following operating systems anymore:
- Windows XP
- Windows Vista
- 32-bit versions of Firefox on Mac OS X.
- Processors older than Pentium 4 or AMD Opteron on Linux.
Mozilla plans to support the last working version for XP and Vista for some time going forward though. Users are migrated automatically to Firefox ESR, the Extended Support Release version of Firefox.
Mozilla plans to support XP and Vista versions of Firefox at least until September 2017. The organization plans to reveal the date supports end at the time, and will base it on the number of users who are still using XP or Vista.
Quantum Compositor on Windows
Mozilla Firefox 53.0 ships with a new GPU Process (Quantum Compositor) on supported Windows devices which reduces driver related crashes by 17%, Direct3D related crashes by 22%, and Direct3D accelerated video crashes by 11%.
Machines need to match the following requirements:
- Windows 7 SP1 or up.
- Multi-process enabled.
- non-blacklisted graphics card.
That's about 25% of users according to Mozilla. To find out whether that is the case for your device, do the following:
- Load about:support in the Firefox address bar.
- Check for the entries GPUProcessPid and GPIPRocess under Diagnostics.
Compact Dark and Compact Light themes
Firefox 53.0 ships with two new themes that resemble those found in the Developer Edition. Compact Dark and Compact Light are available under Appearance on the about:addons page.
Simply click on the enable button next to one of the themes to activate it. The themes do away with the curved tabs, and change a couple of other interface elements on top of that. Also, Firefox has an official dark theme now that it ships with.
Set default Referrer-Policy
Firefox users may set the default Referrer-Policy in Firefox by editing the network.http.referer.userControlPolicy preference. Basically, what the policy does is determine which referrer information should be included in the Referer header.
- Type about:config in the browser's address bar and hit the Enter-key.
- Confirm that you will be careful if the warning prompt appears.
- Search for network.http.referer.userControlPolicy. Set the value to one of the following supported values:
- 0: no-referrer -- no referer information is included.
- 1: same-origin -- referer will only be sent for same-origin requests.
- 2: strict-origin-when-cross-origin -- full URL when a same-origin request is made, send origin for HTTPS to HTTPS requests, and no header to a less secure destinations.
- 3: no-referrer-when-downgrade (default) -- Referer is sent from HTTPS to HTTPS, but not from HTTPS to HTTP.
The default is used whenever sites don't specify a Referrer-Policy. (see Bug 1304623)
Permission notifications changes
The design of permission notifications that Firefox displays when websites request access to features such as the location has changed.
The dialog wont go away automatically anymore when you click somewhere on the page or switch tabs.
Other Firefox 53.0 changes
- Bookmark Sync reliability improvements.
- JSON Viewer enabled by default.
- Lightweight themes are applied in private browsing mode.
- Media playback on new tabs is blocked until the tab is visible.
- Reader mode displays the estimated reading time of the page.
Search added to large select fields in Firefox.(postponed)
- Support for webm video with alpha.
- Inactive tabs have more space for the title.
- Visual refresh for audio and video controls in Firefox.
- Windows users may select 32-bit or 64-bit versions of Firefox in the stub installer on 64-bit versions of Windows.
Use of a separate content process for file:// urls(See Bug 1323700) (postponed)
- Developer Tools with option to copy full path of CSS elements.
- navigator.plugins and mimeTypes are now unenumerable (See Bug 1270364 and Bug 1270366)
Firefox 53.0 for Android
Out-of-process media decoding
Firefox 53.0 and newer versions of the Firefox browser for Android will handle media decoding out-of-process for improved performance on multi-core systems. (See Bug 1333323)
- Right to Left language support (Arabic, Urdu, Hebrew and Persian).
- Portrait mode supports two column tabs in the new version.
- You may long-press on search suggestions to remove it from the browsing history.
Firefox 53.0.2 was released on May 5th, 2017 to the stable channel. It features the following fixes and changes:
- Form validation errors and date picker panel visibility changes (1341190)
- The non-standard showDialog argument to window.find is now ignored (1348409)
- Security fixes
Firefox 53.0.3 was released on May 19th, 2017 to the stable channel. The new version of Firefox ships with two fixes and one change:
- Fixed hangs when a proxy with NTLM authentication is used (1360574)
- Fixed "excessive resource usage" from the "captive portal detection service" (1359697)
- Bump preloaded security information expiration times (1364240)
Security updates / fixes
Security fixes are published after the release of Firefox 53. We will update the article once Mozilla publishes the update.
- CVE-2017-5433: Use-after-free in SMIL animation functions
- CVE-2017-5435: Use-after-free during transaction processing in the editor
- CVE-2017-5436: Out-of-bounds write with malicious font in Graphite 2
- CVE-2017-5461: Out-of-bounds write in Base64 encoding in NSS
- CVE-2017-5459: Buffer overflow in WebGL
- CVE-2017-5466: Origin confusion when reloading isolated data:text/html URL
- CVE-2017-5434: Use-after-free during focus handling
- CVE-2017-5432: Use-after-free in text input selection
- CVE-2017-5460: Use-after-free in frame selection
- CVE-2017-5438: Use-after-free in nsAutoPtr during XSLT processing
- CVE-2017-5439: Use-after-free in nsTArray Length() during XSLT processing
- CVE-2017-5440: Use-after-free in txExecutionState destructor during XSLT processing
- CVE-2017-5441: Use-after-free with selection during scroll events
- CVE-2017-5442: Use-after-free during style changes
- CVE-2017-5464: Memory corruption with accessibility and DOM manipulation
- CVE-2017-5443: Out-of-bounds write during BinHex decoding
- CVE-2017-5444: Buffer overflow while parsing application/http-index-format content
- CVE-2017-5446: Out-of-bounds read when HTTP/2 DATA frames are sent with incorrect data
- CVE-2017-5447: Out-of-bounds read during glyph processing
- CVE-2017-5465: Out-of-bounds read in ConvolvePixel
- CVE-2017-5448: Out-of-bounds write in ClearKeyDecryptor
- CVE-2017-5437: Vulnerabilities in Libevent library
- CVE-2017-5454: Sandbox escape allowing file system read access through file picker
- CVE-2017-5455: Sandbox escape through internal feed reader APIs
- CVE-2017-5456: Sandbox escape allowing local file system access
- CVE-2017-5469: Potential Buffer overflow in flex-generated code
- CVE-2017-5445: Uninitialized values used while parsing application/http-index-format content
- CVE-2017-5449: Crash during bidirectional unicode manipulation with animation
- CVE-2017-5451: Addressbar spoofing with onblur event
- CVE-2017-5462: DRBG flaw in NSS
- CVE-2017-5463: Addressbar spoofing through reader view on Firefox for Android
- CVE-2017-5467: Memory corruption when drawing Skia content
- CVE-2017-5452: Addressbar spoofing during scrolling with editable content on Firefox for Android
- CVE-2017-5453: HTML injection into RSS Reader feed preview page through TITLE element
- CVE-2017-5468: Incorrect ownership model for Private Browsing information
- CVE-2017-5430: Memory safety bugs fixed in Firefox 53 and Firefox ESR 52.1
- CVE-2017-5429: Memory safety bugs fixed in Firefox 53, Firefox ESR 45.9, and Firefox ESR 52.1
Additional information / sources
- Firefox 53 release notes
- Firefox 53.0.2 release notes
- Firefox 53 Android release notes
- Add-on compatibility for Firefox 53
- Firefox 53 for developers
- Site compatibility for Firefox 53
- Firefox Security Advisories
- Firefox Release Schedule
Now Read: The state of Mozilla Firefox