Flash Player version 11.3.300.268 includes several bug fixes. A month ago, Firefox (and non-IE browsers) got its own update to try fixing Flash Player crashes in Firefox 13 but, for many users, the crashes have continued through to Firefox 14 too.
Adobe had another go at fixing the problem earlier this month with a new version for both IE and Firefox/others (on Windows and Mac) – bringing them back into line with the same version number for each. That still didn’t fix all issues relating to the new Sandbox mode in Firefox. Now Adobe are having another (hopefully final!) go at fixing the problem. New features include:
Fixes – this release includes bug fixes related to general stability, audio, and video – specifically, Flash Player content not rendering correctly on Firefox on Windows in Sandbox mode and various general stability issues.
Known issues – Audio distortion issues when streaming Flash content. The full change log is available from Adobe here.
If you previously enabled ‘automatic background updates’, your Flash Player may already have received this update – skip to the ‘How To Test Flash Player’ section below to check if you have this new version. If the update has not yet been applied automatically or you do not have automatic Flash Player updates enabled:
- Download and install Flash Player 11.3.300.268 directly from Adobe here.
- During installation, untick the additional ‘freebie’ (Google Toolbar or McAfee Security Scan) unless you want that as well.
- After installation completes, choose your update method from the following options (picture is from 11.2 but it’s exactly the same in 11.3):
Flash 11.3 – Choice Of Update Method
- It is recommended to choose ‘Install updates automatically’ to ensure that future security and feature updates are installed as soon as they are available.
If chosen, the automated installation of future Flash updates will be ‘silent’ i.e. no notifications will appear before, during, or after an update is performed by the Flash Player Background Updater – so there will be nothing for the user to do and Flash should keep itself updated in future 
How To Test Flash Player? Open your web browser and visit the Adobe Flash Player test page to check that Flash 11.3.300.268 is now properly installed and working.
Issues With Firefox 14? Firefox 14 (and 13) has had many issues with Flash crashing which Adobe have now tried to fix several times. This version may or may not help – in announcing this new version, Adobe state: “it’ll be helpful if you can download and install the Firefox 15 “Aurora” release and submit all crash reports when they occur“. Which doesn’t sound too promising…
Tip: if you previously disabled Adobe’s new Protected Mode (sandbox) for Firefox you should now enable it again for best security by editing the mms.cfg file again – see here for instructions.
If This Version Does Not Fix Firefox Crashes – follow Adobe’s advice from the last version – “Adobe has developed a patched version of Flash Player 10.x – Flash Player 10.3.183.20, which can be downloaded here“. Patched means that it has all the most recent security updates so is safe to use, albeit without the newer features of version 11.
The link leads to archived versions for developers. Scroll down to the ‘Release and Content Debugger Archives’ and download the 10.3.183.20 zip archive then close Firefox. Unzip the archive and browse to the 10.3.183.20 folder then run the uninstall_flash_player_win.exe utility to remove the current faulty Flash 11.3 version. Now install Flash for Firefox – the file is named flashplayer10_3r183_20_win.exe
Hopefully a future update will fix version 11.3 at some point but for now version 10.3 is up to date and works ok…
Conclusion
This update includes stability and bug fixes for all browsers (especially Firefox) and applies to Windows and Macs. It may help resolve some problems introduced by version 11.3 but it may still be necessary for some users to revert back to 10.3 if necessary.
