Question
People commonly ask on the Zoom Developer Forum:
When joining a meeting with the Web Meeting SDK (v4.0.7), I intermittently get “Cannot read properties of undefined (reading ‘caps’)” at lM.getLocalRecordingPermissionUserList. Sometimes the meeting still works after dismissing the error. What causes this and how can I fix it?
Answer
This is a known Web SDK behavior on the local-recording permission path: the error can occur when the host isn’t in the meeting yet or meeting metadata isn’t ready. It’s often seen when join-before-host is enabled and a participant/bot joins first.
Recommended steps:
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If you’re not doing recording, remove or skip any local-recording permission helpers. The Web Meeting SDK does not support local recording.
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If you need the compliance prompt, only call
mediaCapturePermissionafter you are fully in-meeting and the host is present. -
Add guards for undefined state before accessing capability fields (e.g., check objects exist before reading .caps).
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If possible, have the host join first or delay permission-related logic until host presence/metadata is confirmed to avoid the undefined caps state.
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