Helping with crashes

Revision Information
  • Revision id: 36754
  • Created:
  • Creator: AliceWyman
  • Comment: removed suggestion to ask ''Cww'' (Cheng) or ''zzxc'' (Matthew) for help.
  • Reviewed: Yes
  • Reviewed:
  • Reviewed by: Verdi
  • Is approved? Yes
  • Is current revision? No
  • Ready for localization: Yes
  • Readied for localization:
  • Readied for localization by: Verdi
Revision Source
Revision Content

When Troubleshoot Firefox crashes (closing or quitting unexpectedly) and a user asks for help, viewing the crash report will help you to better understand the cause of the crash (for example, extensions or third party software) and provides useful information needed to find a solution, such as related bug reports. This article describes that troubleshooting process.

How do I look up someone's crash report?

When people visit the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article or work through the Ask a Question flow, we ask them to copy their latest Crash ID from about:crashes and to paste it into the question form. When you are trying to help them on the support forum, you can look up their crash report like this:

  1. Click the More system details... link to open the Additional System Details dialog.
  2. Copy the Crash ID.
    crash1
  3. Go to crash-stats.mozilla.org, paste the Crash ID in the search box and hit Enterreturn on the keyboard. This should bring up the crash report.
    crash2
Note: Instructions for users to find their Crash ID are in the Firefox crashes article. Those instructions are also handy if you are helping someone in person.

How do I read a crash report?

A crash report contains many useful pieces of information. This explains what to look for.

The report always begins on the Details tab. The big thing you want to check for here is the Related Bugs section. If this section exists, it will link you to bugs related to this crash signature. Click though and read the bug report — especially all of the comments. What you are looking for is a workaround that you can give to the person you are trying to help.
crash3
Also if the status of the bug is FIXED, look at the Target Milestone and Tracking Flags fields. They will tell you in which version of Firefox the issue has been fixed.

Check for malware

If there were no related bugs, click on the Modules tab. Here you're looking for files with no version information. They are sometimes related to malware. Often googling the name of the file will help you corroborate this. If malware is suspected, recommend that people download and run both Malwarebytes and SUPERAntiSpyware. You should also link them to the Troubleshoot Firefox issues caused by malware article.
crash4

Check for problem extensions

Finally, check the Extensions tab to see what (if any) extensions were running. You'll probably have to google the Extension ID to figure out what some of them are but that should also pull up information about extensions that often cause problems. If you suspect a problem extension, recommend that they disable that extension and see if the problem is fixed (instructions are in Use extensions to add features to Firefox). You should also link them to Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems in case that doesn't work.
crash5

Other helpful parts of a crash report

  • Details tab:
    • Signature - Describes the kind of crash. There are links in this field that will let you view every crash report with the same crash signature over 1 - 4 weeks across all Firefox versions.
    • In addition to the crash signature, the top section contains details about the crash time, crash reason, Firefox version, OS, CPU, graphics settings, and the LSP.
    • Crashing Thread - Shows the last function calls before the crash. You can see if third party software is implied. The bug component is usually the component which the last called functions belongs to.
  • Comments tab: User's comment written when Mozilla Crash Reporter was opened and may help to understand how it takes place.
  • Correlations tab: Tables of correlation data (modules, add-ons, CPU cores) for this crash signature and reason elaborated from all the crashes of the day in the current Firefox version. The higher the ratio is between the two percentages, the higher the correlation is. Correlations per module and per add-on must be checked to see if it's caused by third party software or add-ons.

What do I do if I need help reading crash reports?

Crash reports contain a lot of very technical information. There are many more things that can be learned from them than what's presented in this article. And sometimes the steps presented here won't lead to concrete steps you can give a user to fix their situation. If you want help with reading crash reports, the best thing to do is ask for help in IRC. Click here to join the #sumo channel (chat room) Just type: Can someone help me read this crash report?