What's New in Firefox 4
Our Release Candidate is a very important step towards our final release. Since the previous (Beta 5) version, we improved performance even more, and we fixed numerous bugs and added some important features. Based on all the great user feedback we have received, we have continued to focus on making the browser faster, more stable, and more usable with this version:
- There are now over 150 add-ons for Firefox for mobile, and counting. Dozens of add-ons are already compatible with our latest browser version. Thanks to our awesome community, the number of exciting compatible add-ons increase constantly. Check out the winners of our Mobile Add-on Cup and many other amazing extensions for your mobile browser.
- Performance and Memory Usage
- We improved startup speed even more (compared to previous Beta versions). This was a top user request.
- Improved page load speed
- In Beta 5 we introduce the feature to move Firefox to the SD card along with all its profile data (requires Android 2.2 or higher). This reduces memory usage on your mobile device to a minimum and leaves more space for other apps.
- Scrolling and page rendering are significantly faster and much smoother, showing far less checkerboarding. Smarter page rendering and page loading algorithms led to this very visible improvement.
- Reducing memory and optimizing CPU usage are ongoing themes. We have been working on improvements in this area to make the browser more responsive and stable. Overall responsiveness has improved. With this version, we have implemented additional optimizations that speed up the browser and make it much more responsive, especially when using Firefox Sync. You will see continuous improvement in our future releases
- User Interface
- Filling out forms is now easier than ever with our improved Form Assistant: tapping into form fields zooms you in swiftly and shows a list of suggested values to make navigation easy and to minimize typing. This is particularly useful when using Firefox Sync, which helps synchronize form data like user names and passwords (and also bookmarks, browsing history) across your connected devices, so you never have to type a user / password or other form fill data twice. The new controls make it very easy to fill in forms in web pages.
- It is now easier to close the sidebars without accidentally reopening them.
- We now support copy and paste for all form fields on web pages.
- We fixed miscellaneous bugs, introduced usability improvements, and optimized the user experience with this release. Firefox 4 for mobile Release Candidate is also more stable than previous versions. See "Known Issues" below for details on fixed bugs
- Japanese is now included in the default set of languages for the Firefox user interface.
- For developers
- NOW is the time to build new awesome add-on or to make all your mobile add-ons compatible with our Release Candidate. Our interfaces are all stable, we don't expect any changes for our final release that would impace add-ons. Go! Find all the tools and resources you need on our Developer Hub
- Firefox 4 adds support for IPv6 on Android.
- The "overflow: scroll" and "overflow: auto" CSS properties are now supported.
- In Beta 4 we introduced restartless add-ons
- Also in Beta 4 we started providing support for HTML5 online/offline events
As well as these features from the previous Firefox Betas:
- Added an option to resize text to fit the screen when you double-tap to zoom in, to optimize the reading experience. This feature can be activated in the Firefox preferences.
- Usability - support for Android hardware and software keyboards, Android-style menus, copy/paste in URL bar, search engines appear in the awesomescreen as you type, browse recommended add-ons through the add-on manager (read more)
- File Handling - Support for uploading files, "Save as PDF" command in the site menu
- Localization - fixed rendering of Arabic and Farsi text (on devices with Arabic/Farsi fonts installed)
- Sync - New UI for simpler setup, support for custom Firefox Sync servers
- Video - Full-screen open video and improved audio performance
- Developers - localStorage API, orientation events
- Sync - Shipping with the Firefox Sync feature built-in, Firefox 4 synchronizes your Firefox history, bookmarks, open tabs, and form data like user names and passwords between your desktop and mobile.
- Add-ons - Firefox 4 offers add-ons, small pieces of software that let you change the look and feel of your Firefox to fit your browsing lifestyle.
- Pinch-to-zoom (Android), double-tap, or use the volume rocker (Nokia N900) to zoom in and out
- Open tabs as thumbnails let you easily see and open the site you want
- Location-Aware Browsing gives you content and info relevant to your location
- Save to PDF in the Site Menu lets you archive important docs like tickets and directions to view offline
- Find in Page in the Site Menu lets you quickly find text on the webpage
- Share Page in the Site Menu lets you send content to email, Facebook, Twitter and Google Reader
- Forget Password in the Site Menu tells a website you no longer trust to forget your private data
- Add Search Engine in the Site Menu lets you quickly add a new search engine to your Awesome Screen
- Context Menu lets you Open in New Tab and Share by long tapping and holding a link
- Smart Tapping lets you tap on links, widgets and other Web content with accuracy
- Password Manager lets you choose to remember site password to avoid typing
Although Firefox for the desktop and mobile are built on the same technology platform, there are differences that will require developers to make changes to their add-ons in order to become compatible with Firefox 4 for Android and Maemo. New: We now support restartless add-ons. Visit the Electrolysis and Add-ons wiki page and the Add-ons Training Week documentation to learn more.What’s under the hood
- The same browser engine as Firefox 4.0 for desktop
- Leading Web compatibility
- Optimized for ARM processors
- Location-Aware Browsing
- Web workers
- Offline storage
- online/offline events
- Native JSON
- Users who have a large desktop profile using Firefox Sync may see some performance issues during the initial sync process. We are working to improve this in future releases.
- Major changes to Firefox for mobile have been made which have resulted in multiple add-ons to break. Developers, please see the Electrolysis and Add-ons wiki and the Add-ons Training Week documentation to help you make your add-on compatible with Firefox.
- Adobe Flash and other plugins are not supported. Currently, enabling the Flash plugin results in a compromised user experience across Firefox for mobile.
- Users cannot edit content within documents or spreadsheets using Google Docs or Etherpad.
- 617298 - There are some issues with SwiftKey that may cause it to crash or to prevent users from entering text in input fields.
- 602252 - Loading some pages in Firefox causes long freezes on some Motorola phones, especially the Motorola Droid (or “Milestone”).
- 535793 - On Nokia N900, Firefox will display an error when connecting to a network and loading a page at the same time.
- 624652 - Under some circumstances, Android 2.3.1 may freeze while running Firefox on the Nexus S. This appears to be fixed by the Android 2.3.3 system update.
- 626051 - Fennec crashes on old nightly builds of Cyanogenmod 7 (an unofficial, community-developed version of Android), and on a few other unofficial Android ROMs.
- 622839 - HTML 5 video may load slowly and create artifacts on the screen during playback.
- 624691 - Maemo users will not be able to open certain file types through the download manager
- 628269 - Pages are zoomed in at reload
Bugs fixed since Firefox 4 Beta 5:
Firefox 4 Release Candidate is available for Android 2.0 and higher, and for the Nokia N900.
Firefox 4 Release Candidate requires 512 MB of RAM and around 14 MB of storage. However, Android 2.2 users can move Firefox and user data to the SD card using Android’s Settings app.
This release requires a phone with an ARMv7 processor. Before installing Firefox 4 on your Android phone, visit the Platforms and Device Requirements page. See a full list of supported and unsupported devices by visiting our System Requirements wiki.
Download Firefox 4 (Release Candidate) by visiting Firefox.com/m on your Android phone or Nokia N900. Visit the Platforms and Device Requirements page to make sure your phone meets the system requirements.
Developers: You can download a version of Firefox for mobile to your desktop in order to test, provide feedback, and build add-ons. Desktop builds are for development purposes only and don't have full functionality:
Frequently Asked Questions
- Is Firefox 4 available for my phone?
- Firefox 4 is available for Android (2.0 or higher) phones with compatible hardware, and for the Nokia N900. See the Android System Requirements to see if Firefox 4 is compatible with your Android device. You can download the Firefox 4 Release Candidate or download Firefox 1.1 for the Nokia N900 at firefox.com/m. If Firefox for mobile is not available for your device or platform, we're continuing to investigate ways to bring parts of the Firefox experience to you. Learn more about our mobile projects.
- Is it called Fennec or Firefox?
- Fennec is the codename of Mozilla’s mobile project, however the official product name is Firefox. Pre-beta releases of Firefox are called by the codename, Fennec.
- How will Firefox keep me safe while I browse on my mobile?
- Mozilla’s open source process leverages the experience of thousands of security experts around the globe, and Firefox includes features like HTTP Strict Transport Security, which lets Firefox work together with web site authors to protect you against eavesdropping and web forgery. Customizable security settings to manage passwords, cookies, loading images and installing add-ons give you complete control over your browsing experience. Learn more.
- How do I use the Firefox user interface to browse the Web?
- To save space on your phone’s display, Firefox browser controls are stowed away to the sides of the screen. Swipe right to access your tabs on the left side of the screen. Swipe left to view one-touch bookmarking, back and forward, and access your browser tools. To let you see more of the Web site, your browser controls and Awesome Bar get stowed away out of view. when you scroll down a Web page, but they instantly reappear if you pan to either side. Tap on the on Web site icon to the left of the Awesome Bar to open the Site Menu and manage your relationship with the current web page.
- What is the Awesome Screen?
- The Awesome Screen pops up just by tapping on the location bar. It instantly brings up a smart list of your favourite history items and bookmarks and lets you easily select a search engine for your desired search. You can also customize your search engine list for maximum efficiency.
- How do I zoom in and out?
- For Android phones, pinch to zoom in and out, or double-tap. For the Nokia N900, you can use the volume button on the top of your phone, or double tap the screen with your finger to zoom in and out. Also, on the Nokia N900, Ctrl-up and Ctrl-down arrows will zoom in and out.
- How do I bookmark a web page?
- Go to the site you wish to bookmark. Touch the bookmark “star” button on the right side of your display.
- How do I open a new tab?
- Touch the new tab "plus" button on the left side of your display screen to open a new tab. Tabs appear as thumbnails so you can easily see which page you’d like to select.
- What are Firefox Add-ons and how can I get them on my mobile device?
- Add-ons are small pieces of software that let you add or change the look or functionality of Firefox. Install add-ons directly to your Firefox by swiping to the left and tapping on the browser tools "gear" button on the bottom right-hand side of your screen, then choosing the add-ons “puzzle piece” button to discover and install the add-ons that are most useful to you.
- How can I share my Firefox bookmarks, history, tabs, and passwords between my desktop and my mobile?
- Firefox Sync is a built-in feature of Firefox 4 that lets you synchronize your desktop and mobile data. To use this feature, you must first install Firefox 4 for the desktop. Then go to Tools, Set Up Sync and follow the prompts to create a Sync Account. Once you have an account on your desktop, go to Firefox on your mobile phone, tap on Browser Tools button. Scroll down the Preferences pane and tap Connect under the Sync section. A one-time code will appear. Go back to your Sync account info, select “Add Device” and enter the code from your phone. Learn more about setting up Firefox Sync on your mobile.
- Do I need to setup Firefox Sync to use Firefox 4 on my phone?
- No. Although we think Firefox Sync is highly useful, it is feature that you can choose to use or not. The Awesome Screen will start to get to know you and take you to your favorite parts of the Web with minimal typing, even without Firefox Sync.
- What are the trade-offs to using Firefox Sync in Firefox 4 (RC)?
- Although we think Firefox Sync is highly useful, it is still in its experimental phase. Those who use Firefox Sync and who have large desktop profiles, may detect performance issues on their mobile. We are working to resolve this in future releases.
- What is Location-Aware Browsing? Is Firefox tracking where I am?
- Location-Aware Browsing saves you time by allowing websites to ask you where you are. If you choose to share your location with a website, it can use that information to find nearby points of interest and return additional, useful data like maps of your area. It’s all optional – Firefox doesn’t share your location without your permission. Learn more about Location-Aware Browsing.
- Will a Firefox add-on I built for the PC work on mobile? If not, do I need to change it?
- Although Firefox for the desktop and mobile are built on the same technology platform, there are differences that will require developers to make changes to their add-ons in order to be compatible with Firefox for mobile. Visit the Mobile Developer Network and Electrolysis and Add-ons wiki to learn more.
- What browser engine does Firefox use?
- How do I develop a Location-Aware website for Firefox?
- Firefox has implemented the first public draft of the Geolocation specification from the W3C. An overview on how to develop Location-Aware websites here.
- Does Firefox on my mobile support HTML 5?
- HTML 5 is the next major revision of HTML. The HTML 5 specification is ongoing, but there are several HTML 5 and related features that will enable Web developers to create more innovative websites and applications. Firefox includes important features like Location-Aware browsing, the <canvas> and <svg> tags, Web workers and offline storage.
- Does Firefox on my phone support plugins?
- There is no plugin support in Firefox 4 for Android, and plugins are disable in Firefox 4 for Nokia N900. On most Web pages that use the Adobe Flash plugin, the performance of the plugin on Nokia N900 didn't meet our standards, and the interactivity and performance of the entire Web page was negatively impacted. This was especially felt on pages with multiple instances of the plugin. Advanced users can enable plugins in Firefox for Nokia N900 for experimentation and testing only.
- How can I get involved?
- Help spread the word, test and improve Firefox 4 and Go Mobile. If you’d like to learn more about ways you can get involved in other mobile-related initiatives, check out our Get Involved page. As always, your input is welcome.