Remote Viewer session stuck on black screen or freezes mid-session: restart session and capture HAR logs to investigate

Android

Title: Remote Viewer shows black screen or freezes — restart session and capture HAR logs

When starting or using Remote Viewer in the Esper Console, the device display either renders as a solid black screen on connect or stops updating mid-session so that taps and button presses produce no visible response.

Why this happens

Remote Viewer relies on a persistent WebSocket connection between your browser and the device. A stale connection, cached session data, or a conflicting browser extension can interrupt the stream before the display renders or cause it to stop refreshing. Restarting the session forces a clean connection; if the problem is browser-side, Incognito mode isolates it.

Step 1: Restart the Remote Viewer session

1. Navigate to Devices & Groups → [Device Name] → Remote Viewer in the Esper Console.
2. If a black screen or frozen frame is visible, click the disconnect or cancel button to fully end the current session.
3. Click Start Session to open a new connection.
4. Confirm the display renders in the correct orientation and that tapping interactive elements produces visible updates. In most cases the session loads correctly on the second attempt.

Step 2: Try Chrome Incognito mode

If the issue persists after restarting, open an Incognito window to rule out browser extensions or cached session data.

• Windows: Press Ctrl+Shift+N
• Mac: Press Cmd+Shift+N

1. Open the Esper Console in the Incognito window.
2. Navigate to Devices & Groups → [Device Name] → Remote Viewer and start a new session.
3. If the session works correctly in Incognito mode, the root cause is a browser extension or cached data in your standard profile — review your installed extensions and clear your browser cache before retrying in a normal window.

Step 3: Capture HAR logs

If the black screen or freeze occurs across multiple restarts and in Incognito mode, capture an HTTP Archive (HAR) log while the failure is actively happening. Logs captured after the issue resolves will not contain the failure state and cannot be used for diagnosis.

1. Open Chrome DevTools by pressing F12 or Ctrl+Shift+I (Mac: Cmd+Option+I).
2. Click the Network tab. Confirm recording is active — the record button should appear red.
3. Navigate to Devices & Groups → [Device Name] → Remote Viewer in the Esper Console and start a new session.
4. Allow the black screen or freeze to occur while the Network tab continues recording. Do not close DevTools or navigate away.
5. Once the failure state is visible, click the Export HAR button (down-arrow icon) at the top of the Network panel to save the .har file.

Verify: The exported .har file should be non-zero in size and timestamped to the moment the failure occurred. Open the file in a text editor and confirm it contains entries — an empty or near-empty file indicates recording was not active during the failure.

If this doesn't resolve it

Contact Esper Support and include the following:

• The .har file captured during the failure
• The Device ID of the affected device, found at Devices & Groups → [Device Name] → Device Details
• Whether the failure is a black screen at startup, a freeze mid-session, or both
• Whether the issue also occurs in Chrome Incognito mode

Still need help?

If the steps above don't resolve the issue, submit a support ticket with your device model, Android version, Esper Agent version, and a description of what you've already tried — this helps the support team investigate without a follow-up.