This article describes why Firefox may start in Troubleshoot Mode (previously known as Firefox Safe Mode) when you expect it to start normally, and how to fix the problem.
- See the Diagnose Firefox issues using Troubleshoot Mode article for information about using this special startup mode to fix Firefox problems.
If you started Firefox in Troubleshoot Mode, it will remain in Troubleshoot Mode until Firefox is completely closed. The easiest way to make sure Firefox is completely closed is to restart your computer. Once your computer starts up again, start up Firefox.
When Firefox crashes at startup, the next time you launch Firefox, it displays the Troubleshoot Mode window. This lets you choose between starting in Firefox Troubleshoot Mode or refreshing Firefox because you may have something wrong with your configuration (such as graphics, add-ons, or third-party software). See Troubleshoot Firefox crashes (closing or quitting unexpectedly) for help to solve crashes when starting Firefox.