Firefox (Windows/macOS)
Fix Webcam Not Working in Firefox
Allow camera access in Firefox, select the right device, and confirm with the DevicePrep Webcam Test.
Use the DevicePrep Webcam Test to verify Firefox can access your camera.
If Firefox won’t show your camera, it’s usually a blocked site permission, the wrong camera selected, or another app already using the lens. Start with a quick Webcam Test to confirm Firefox can display any video, then clear the block list and lock Firefox to the right camera.
What this guide covers
- Firefox won't ask for camera permission when you open a meeting site
- Firefox camera permission is allowed but the preview stays black
- The webcam works in Chrome but not Firefox (or vice versa)
Quick wins (2 minutes)
- In the Firefox permission prompt, choose your camera and click Allow (not Block).
- Click the camera icon near the address bar and remove any saved “Blocked” permission for the site.
- Quit Zoom, Teams, Meet, FaceTime, and OBS so Firefox can claim the camera.
- macOS: System Settings -> Privacy & Security -> Camera -> enable Firefox.
- Windows: Settings -> Privacy & security -> Camera -> allow Firefox and allow desktop apps.
- Restart Firefox after changing permissions so the camera prompt resets.
Step-by-step fix
- Open the DevicePrep Webcam Test in Firefox and click Allow when prompted.
- If you don’t get a prompt, open Firefox Settings -> Privacy & Security -> Permissions -> Camera -> Settings and remove the site from blocked/allowed lists.
- Reload the page, then choose the correct camera in the Firefox prompt (internal vs USB) and click Allow.
- Quit other apps that might be using the camera, then retest.
- Confirm OS permissions: macOS Camera permission for Firefox; Windows camera privacy toggles enabled.
- Update Firefox and reboot if the camera stays black or never appears.
- When the Webcam Test preview is stable, open your meeting app in Firefox and select the same camera.
Deep fixes
Run a live webcam check in Firefox first
Open the DevicePrep Webcam Test in Firefox and look for a preview. If you see video, your camera and Firefox pipeline are working and the issue is inside your meeting site or app settings. If you see a gray box or black screen, keep the test open while you adjust permissions so you can see changes instantly. If the permission prompt never appears, Firefox likely has a saved block that must be removed.
Remove blocked site permissions in Firefox
Firefox stores camera decisions per site. Open Settings -> Privacy & Security, scroll to Permissions, and click Settings next to Camera. Remove the site from any blocked list so Firefox can prompt again. You can also click the camera icon near the address bar (when present) to review and clear permissions for the current site. Reload after changes; Firefox only re-asks after a refresh.
Choose the correct camera device
When Firefox prompts, it may list multiple cameras: the built-in webcam, a USB webcam, or a virtual camera. Choose the camera you actually want, then click Allow. If you are not sure which is which, unplug the USB camera and reload to see which entry disappears, then plug it back in. For troubleshooting, disable virtual cameras (OBS Virtual Camera, Snap Camera) so you can confirm the real webcam works first.
Check OS permissions and camera conflicts
On macOS, Firefox needs Camera permission in System Settings -> Privacy & Security -> Camera. Toggle it on, then quit and reopen Firefox so it takes effect. On Windows, enable camera access under Settings -> Privacy & security -> Camera and allow desktop apps. Also close apps that commonly hold the lens (Zoom, Teams, Meet, FaceTime, OBS). If the webcam LED stays on after you close everything, rebooting resets the camera session quickly.
Update and retest before your meeting
Update Firefox (Menu -> Help -> About Firefox) and apply any pending update; older builds can get stuck with device prompts. After updating, rerun the Webcam Test and watch the preview for 30 seconds to confirm stability. If the camera flickers, move USB webcams off hubs and onto a direct laptop port. Once the preview is stable, open your meeting site and select the same camera so the app doesn’t fall back to the wrong device.
Quick checklist
- Firefox prompts for camera access (or the site is unblocked in settings)
- Camera permission set to Allow for the site
- Webcam Test shows live video in Firefox
- OS camera permission granted to Firefox
- No other app is holding the camera
- Correct camera selected in your meeting site/app
FAQs
Why does the camera work in Chrome but not in Firefox?
Firefox has its own per-site permission list and may be blocked even if Chrome works. Remove the saved block in Firefox Camera permissions, reload, and click Allow.
Why does Firefox show “No camera found”?
If the OS can’t see the camera, Firefox can’t list it. Unplug/replug USB webcams, try another port, and restart the computer to refresh the driver.
Can Firefox privacy settings block the camera?
Yes. Strict tracking protection or privacy extensions can interfere with prompts. Test in a clean profile or temporarily disable extensions to compare.
Does Incognito/Private mode change camera access?
It can. Private windows may prompt differently and some extensions behave differently there. If it fails in Private, test in a normal window too.
Sources
Documentation referenced while maintaining this guide.
Wrap up
Clear Firefox’s camera blocks, grant OS permission, and confirm with the Webcam Test before your call. Once the preview is stable, run the Pre-Call Checklist to verify mic and speakers too.