USB Webcam Compatibility with LockDown Browser on Mac (Logitech, Razer, Generic)

Last updated 2026-05-02 · LDBypass Editorial

Quick compatibility table

Why external webcams sometimes fail

Three failure modes:

1. TCC Camera permission grants for the wrong device. macOS's TCC system grants per-app, not per-camera. LDB has Camera permission; whichever camera is selected as system default is the one Monitor uses.
2. AVFoundation property mismatch. Some webcams expose unusual capture format combinations. Monitor's face-detection pass requires specific YUV formats; some webcams default to formats that the detector doesn't handle.
3. Driver / companion app required. Logitech BRIO 4K, Razer Kiyo Pro, and Insta360 Link all benefit from their companion apps to set the correct mode before LDB launches.

Selecting the correct webcam before LDB launches

The system default camera is what Monitor uses. To set it:

1. Quit LDB if running.
2. Open FaceTime (or Photo Booth if you prefer).
3. Menu bar: Video → select your preferred camera.
4. macOS persists this selection across apps that don't have their own camera picker.
5. Quit FaceTime / Photo Booth (you don't want them running during the exam - they may hold the camera).
6. Launch LDB. The system check uses the camera you just selected.

Logitech BRIO 4K specifically (Sequoia 15.4+)

The most reported compatibility issue in 2026. Symptom: BRIO 4K shown in System Settings → Privacy → Camera; LDB has permission; but Monitor's system check fails with "Camera not detected".

Cause: macOS Sequoia 15.4 changed AVFoundation property exposure for cameras with multiple sensor modes. Logitech's BRIO 4K driver requires a one-time initialization from Logi Tune (Logitech's utility) before TCC reflects the camera correctly.

Fix:

1. Download Logi Tune from logitech.com/software/logitune.
2. Install + launch once.
3. In Logi Tune, confirm the BRIO 4K is recognized.
4. Quit Logi Tune.
5. Launch LDB. The BRIO 4K now responds correctly.

Razer Kiyo Pro caveat

Kiyo Pro's adaptive HDR + auto-exposure can confuse Monitor's face detection in challenging lighting. Symptom: face flagged as missing intermittently during exam.

Mitigations:

• Install Razer Synapse and disable Adaptive Light Sensor.
• Set fixed exposure compensation in Razer Synapse before exam.
• Use plain front-facing lighting (see facial detection page).

Generic / no-name webcams

Cheap "1080p USB webcam" cameras from Amazon often miss critical AVFoundation capabilities. Symptoms: webcam works in Photo Booth but Monitor's face-detection times out.

Three options:

1. Use the built-in MacBook camera instead. Almost always reliable.
2. If you must use external: borrow a Logitech C920 or similar - that family is known-compatible.
3. Test in advance with the practice exam your instructor enabled.

Continuity Camera (iPhone as webcam)

Supported since macOS Ventura 13.0+ + iOS 16+. Procedure:

1. Sign in to the same Apple ID on Mac and iPhone.
2. iPhone must be near the Mac (Bluetooth + Wi-Fi range).
3. iPhone is unlocked OR in the special Continuity Camera mode.
4. Open FaceTime → Video → select your iPhone.
5. Quit FaceTime; launch LDB. Monitor uses iPhone as the camera.

Caveat: iPhone may go to sleep mid-exam if you don't set it to "stay on while connected". Battery drain on iPhone during a 90-min exam is ~30%.