Firefox crashes or displays text and page elements incorrectly
What to do first
Use Troubleshoot Mode to distinguish GPU effects from extension effects, and disable acceleration only when needed.
This is a general troubleshooting guide, not an announcement of a current outage.
Affected products and symptoms
- Product
- Mozilla Firefox
- Versions and conditions
- Firefox Desktop (general Mozilla support procedure; no specific version)
Symptoms
- Firefox crashes
- Text or objects on web pages display incorrectly
Causes and conditions
With some GPU and graphics-driver combinations, Firefox hardware acceleration can contribute to crashes or rendering problems.
Before you start
- Save open tabs and work
- Update Firefox to the latest version
- Record the current settings under General > Performance
Precautions
- Improvement in Troubleshoot Mode does not by itself prove that the GPU is responsible
- Disabling acceleration may affect video playback or rendering performance
Tools and official pages used in this guide
Review the startup procedure and the features disabled in diagnostic mode.
Step-by-step instructions
Choose Menu > Help > Troubleshoot Mode > Restart > Open. This opens a diagnostic session with add-ons, themes, and hardware acceleration temporarily disabled.
This makes no permanent change, so reproduce only the affected page and action and record the result.
Use the three-line menu at the upper right to open the listed items, and distinguish the normal window from the diagnostic one. Use the same URL, zoom level, video position, and action so the before-and-after conditions match.
Official links for this step
- Firefox Troubleshoot Mode
Review the startup procedure and the features disabled in diagnostic mode.
Check before continuingThe official Firefox Troubleshoot Mode page or signed distribution opens, and its product, OS, and version requirements match this computer.
- Firefox Troubleshoot Mode
If the issue persists in Troubleshoot Mode, the disabled features are less likely to be the main cause. Restart Firefox normally to end this guide's temporary changes.
If it improves, do not immediately conclude that the GPU is responsible. After restarting normally, disable extensions and compare the reproduction.
Troubleshoot Mode changes extensions, themes, and hardware acceleration together. Return to normal mode and test the candidates one at a time.
Start normally and open Menu > Settings > General > Performance. Clear Use recommended performance settings, then clear Use hardware acceleration when available.
Quit Firefox completely, reopen it, and test the rendering fault and crash with the same URL, zoom level, video, or scrolling action.
After changing the setting, close every Firefox window and restart. Save the Graphics section of about:support if needed. Restore any setting that does not help before proceeding.
If there is no improvement, restore both check boxes on the same page and restart. If it improves, check for an official GPU-driver update; after updating, enable acceleration again and compare.
If an extension is a candidate, open Menu > Add-ons and themes > Extensions, disable extensions one at a time, and reproduce the issue after each change.
When finished, test another normal page and a video as well as the affected URL. Completion means the rendering fault is gone, the crash does not recur, and any responsible extension has been identified.
Completion criteria: confirm a reproduction difference between Troubleshoot Mode and normal mode, and that the rendering problem or crash stops with acceleration disabled. If unmet, do not repeat the same operation; follow the next branch: restore the recommended-performance and acceleration settings under General > Performance to their original values.
Check before continuingDecision: if there is no improvement, restore both settings and restart. If it improves, install an official GPU-driver update, enable acceleration again, and compare. If an extension is suspected, disable extensions one at a time and retest after each change.
Check the result
- There is a reproduction difference between Troubleshoot Mode and normal mode
- The rendering problem or crash stops after hardware acceleration is disabled
If the problem continues
- If there is no improvement, restore the recommended-performance and acceleration settings under General > Performance
- Disable extensions one at a time and re-enable the others after finding the cause
- Proceed to the Firefox Refresh article only when the entire profile is suspect
Scope of this guide
Troubleshooting guide — This is Mozilla's diagnostic procedure and workaround, not a notice that a particular bug has been fixed.
Frequently asked questions
Can I restore the setting?
Enable acceleration or recommended performance settings again on the same Performance page, then restart Firefox.
Official sources and dates
Source publication or resolution date: 2026-06-12. Sources checked: 2026-09-05. The check date is not the date the problem first occurred. Interface labels can vary between versions and display languages.
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