jitsi/jitsi-meet · error · Error

A remote participant must be associated with a JitsiConferen

Error message

A remote participant must be associated with a JitsiConference!

What it means

participantJoined throws when it is called with a participant object that has no conference property, because remote participants are keyed by an id-conference pair in the participants reducer. This is a programmer/contract error inside the app (an invariant violation), not an environmental failure: the action creator requires every remote participant to be tied to a concrete JitsiConference instance.

Source

Thrown at react/features/base/participants/actions.ts:235

 *     type: PARTICIPANT_JOINED,
 *     participant: IParticipant
 * }}
 */
export function participantJoined(participant: IParticipant) {
    // Only the local participant is not identified with an id-conference pair.
    if (participant.local) {
        return {
            type: PARTICIPANT_JOINED,
            participant
        };
    }

    // In other words, a remote participant is identified with an id-conference
    // pair.
    const { conference } = participant;

    if (!conference) {
        throw Error(
            'A remote participant must be associated with a JitsiConference!');
    }

    return (dispatch: IStore['dispatch'], getState: IStore['getState']) => {
        // A remote participant is only expected to join in a joined or joining
        // conference. The following check is really necessary because a
        // JitsiConference may have moved into leaving but may still manage to
        // sneak a PARTICIPANT_JOINED in if its leave is delayed for any purpose
        // (which is not outrageous given that leaving involves network
        // requests.)
        const stateFeaturesBaseConference
            = getState()['features/base/conference'];

        if (conference === stateFeaturesBaseConference.conference
                || conference === stateFeaturesBaseConference.joining) {
            return dispatch({
                type: PARTICIPANT_JOINED,
                participant

View on GitHub (pinned to 98de6219cc)

Solutions

1. Pass the JitsiConference instance on the participant: participantJoined(dispatch, { id, conference, ... }) — audit the call site listed in the stack trace.
2. If the participant is genuinely local, use localParticipantJoined (or the local variant of the action) instead of participantJoined.
3. When consuming USER_JOINED events, guard: if (!conference) return; before building the participant payload.
4. If synthesizing virtual participants (screenshare/whiteboard), attach the active conference from redux state (getConference(state)).

Example fix

// before
participantJoined(fakeId, {
    id: fakeId,
    name: 'Virtual participant'
});

// after
participantJoined(fakeId, {
    id: fakeId,
    name: 'Virtual participant',
    conference: getConference(store.getState())
});

const isRemoteParticipantPayload = (p: { conference?: JitsiConference }) => Boolean(p.conference);

function isRemoteParticipant(p: { conference?: unknown }): p is { id: string; conference: JitsiConference } {
    return typeof p.id === 'string' && p.conference instanceof Object && 'lock' in (p.conference as JitsiConference);
}

try { dispatch(participantJoined(id, participant)); } catch (e) { logger.error('Malformed participant payload, missing conference', participant); }

When it happens

Trigger: Calling participantJoined({ id, ... }) without a conference field; constructing a fake/virtual participant manually and forgetting to attach the JitsiConference; lib-jitsi-meet firing USER_JOINED with a null/undefined conference argument (e.g., virtual screenshare or whiteboard synthetic joins in older versions).

Common situations: New integration code (e.g., custom virtual participants like the handleSharingVideoStatus or focusWhiteboard callers listed) that passes a plain object without conference; upgrading lib-jitsi-meet where the USER_JOINED payload shape changed; tests/mocks that create participants without a conference stub.

AI-assisted analysis of jitsi/jitsi-meet@98de6219cc (2026-08-28). Data as JSON: /api/errors/02775698d0cf897e. Report an issue: GitHub.