You are viewing information archived from on 2013-08-16.

This is the fourteenth development milestone and the first alpha release of the mobile version of Firefox, codenamed 'Fennec,' on the Windows Mobile 6 platform. This release is provided for for testing purposes only, intended to:

  • get wider feedback on our approach to the user experience;
  • engage Mozilla community teams, including localizers, and testers;
  • get feedback from Web developers;
  • encourage add-on developers to port existing add-ons and invent new ones for mobile.

The initial focus of Fennec development was on building a new user experience that reflects Firefox's design principles, adding touch screen support and other interactions appropriate for mobile phones and other handheld devices. Fennec preserves leading features like the Smart URL Bar ("awesome bar") and support for add-ons.

This alpha release on Windows Mobile focuses on stability, performance, and integration with the Windows Mobile OS. We've reduced our memory usage and begun to adapt our look and feel to smaller screen sizes. This version also includes TraceMonkey, our new high-performance Javascript technology.

To help out, visit the Mozilla mobile page to learn about our public weekly meetings, how to find our community on IRC, and more.

These release notes provide a "quick start" for the impatient, some highlights of what's included in this version, download and installation instructions, known issues, and frequently asked questions. Please read these notes and the bug filing instructions before reporting bugs to Bugzilla.

Quick start

This release is available for the Windows Mobile 6 software platform. If you're viewing this on an Windows Mobile device, install Fennec.

Don't have a Windows Mobile device? Don't worry, you can still experiment with Fennec, provide feedback, write add-ons, and get involved by installing a version of Fennec for your desktop PC:

While the destkop versions of Fennec are not supported products, they are a great way to familiarize yourself with the Fennec UI, provide feedback, build add-ons, or even localize it to your native language.

What's in this version?

New in this release:

  • New Add-Ons Manager
  • New Downloads Manager
  • New CSS based theme
  • TraceMonkey, Mozilla's new JavaScript engine
  • jemalloc, the memory management library used by Mozillla.
  • Faster application start-up time
  • Faster panning
  • Faster zooming
  • Initial implementation of bookmark folders and bookmark editing

This builds upon the feature set of previous milestone releases:

Easy navigation to Web content:

  • Bookmarks, including tags
  • Smart URL bar ("awesome bar")
  • Tabbed browsing with thumbnail images
  • Integrated Web search - built into the URL bar
  • Easy access to multiple search engines

Web content:

  • Maximize content by auto-hiding controls and URL bar
  • Zoom in and out


  • Instant Web site ID ("Larry")
  • Password manager
  • Popup blocker
  • Clear private data

Devices services integration:

  • Click on a phone number to initiate a call


  • Searchable download manager
  • Preferences pane
  • Add-ons manager, including ability to directly find and install add-ons

Installing Fennec

System requirements:

  • Windows Mobile device running Windows Mobile Professional 6.0 of greater.


Install a version of Fennec for your desktop PC:

Tips and tricks

  • swipe left to expose back/forward/bookmark buttons and the URL bar; swipe right to dismiss them
  • swipe right to expose tabs; swipe left to dismiss them

Known issues

  • Bug 458741: Allow panning/scrolling in iframes - Websites that display large amounts of content in IFrames, including Google Mail and Reader, will be very hard, if not impossible, to use.
  • Plugins may not work in some of the desktop builds.
  • Bug 492880: Extension Manager UI is too wide in portrait orientation
  • Bug 492828: Sometimes clicking on a link will highlight the link bug not navigate to it
  • Bug 492827: Selected link highlight takes too long
  • Bug 479753: viewport should dynamically resize based on window size - Page is layed out wider than the screen in many cases forcing the user to pan horizontally to read text.
  • Bug 492111: Cannot accept/decline invalid certificate - The buttons to accept or dismiss an invalid certifacate are placed outside of the viewport and it is not possible to pan them into view.
  • Bug 492084: Sometimes canvas doesn't paint after page load until the user pans or clicks - Occationally a web site will load completely (as indicated by the throbber) but the previously rendered page will still be displayed. Clicking or panning the page causes the current page to be displayed
  • Bug 492073: Identity info doesn't update after tab switch
  • Bug 489589: Password Manager fails on Windows Mobile - The meta data table in our sqllite database is not being initialized correctly, causing sdb_PutMetaData to fail.

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