It depends on your system. Some graphics card drivers are not compatible with the Flash plugin, and some configuration of Windows are not compatible with the plugin's protected mode feature. If you have these problems, then "the fixes" are the best solution. I'm not sure what you've tried, but here are those two: (1) Disable the Flash plugin's use of hardware acceleration See this support article from Adobe: http://helpx.adobe.com/flash-player/kb/video-playback-issues.html#main_Solve_video_playback_issues (2) Disable the protected mode feature The following pages provide different ways to do that: * Adobe support article under the heading "Last Resort": [http://forums.adobe.com/message/4468493#TemporaryWorkaround Adobe Forums: How do I troubleshoot Flash Player's protected mode for Firefox?] * Manual steps: https://support.mozilla.org/questions/968190?page=5#answer-509209 * Batch file to automate the manual steps: https://support.mozilla.org/questions/982093#answer-518078 ---- For personalized troubleshooting, consider replying with links to your crash details. When Firefox crashes, it usually records information about what was happening at that moment. You can submit that data to Mozilla and share it with forum volunteers to see whether it points to the solution. Please check the support article "[[Firefox Crashes]]" (especially the last section) for steps to get those crash IDs, and then post some of the recent ones here.