Hello joychen, in what operation system, we are blind without more details :-) In order to assist you better, please follow the steps below to provide us crash IDs to help us learn more about your crash. #Enter ''about:crashes'' in the Firefox address bar and press Enter. A Submitted Crash Reports list will appear, similar to the one shown below. #Copy the '''5''' most recent Report IDs that start with '''bp-''' and then go back to your forum question and paste that into the "Post a Reply" box. (Please don't take a screenshot of your crashes, just copy and paste the ID's. The below image is just an example of what your Firefox screen should look like) [[Image:aboutcrashesFx29|width=520]] <br><br> More information and further troubleshooting steps can be found in the [[Firefox crashes - Troubleshoot, prevent and get help fixing crashes]] article. thank you