[Due for payment 2026-04-14] Thread - Join button appears briefly, when a user starts thread in a message from another user

[lanitochka17]

If you haven’t already, check out our contributing guidelines for onboarding and email contributors@expensify.com to request to join our Slack channel!

---

Version Number: v9.3.22-2
Reproducible in staging?: Yes
Reproducible in production?: Yes
If this was caught during regression testing, add the test name, ID and link from BrowserStack: https://test-management.browserstack.com/projects/2219752/folder/13177078/test-cases/41237893?sort=%2Bidentifier
Email or phone of affected tester (no customers): n/a
Issue reported by: Applause Internal Team
Bug source: Regression TC Execution
Device used: Mav 15.4.1 Safari/Chrome, iPhone 13 ioS 26.2.1
App Component: Chat Report View

Action Performed:

1. Go to https://staging.new.expensify.com
2. Go to a chat with another user
   3.Start a thread in a message sent by another user

Expected Result:

Verify you're redirected to the thread conversation, the Join button should not appear

Actual Result:

Join button appears briefly, when a user starts thread in a message from another user

Workaround:

Unknown

Platforms:

• Android: App
• Android: mWeb Chrome
• iOS: App
• iOS: mWeb Safari
• iOS: mWeb Chrome
• Windows: Chrome
• MacOS: Chrome / Safari

Screenshots/Videos

Bug7082489_1771511737248.ScreenRecording_02-18-2026_23-13-43_1.mp4

View all open jobs on GitHub

Issue Owner

Current Issue Owner: @aimane-chnaif

[melvin-bot]

Triggered auto assignment to Contributor-plus team member for initial proposal review - @aimane-chnaif (External)

[melvin-bot]

Triggered auto assignment to @twisterdotcom (Bug), see https://stackoverflow.com/c/expensify/questions/14418 for more details. Please add this bug to a GH project, as outlined in the SO.

[melvin-bot]

Unable to auto-create job on Upwork. The BZ team member should create it manually for this issue.

[MobileMage]

Proposal

Please re-state the problem that we are trying to solve in this issue.

When a user starts a thread on another user's message, a "Join" button briefly flashes in the header before disappearing.

What is the root cause of that problem?

When createChildReport builds the optimistic thread report, it calls getChildReportNotificationPreference(parentReportAction) to determine the notification preference. Since the parent message was authored by a different user, isActionCreator returns false, so the preference resolves to HIDDEN. This HIDDEN value is then passed to buildOptimisticChatReport, which applies it uniformly to all participants -- including the current user who is creating the thread. When HeaderView renders, canJoinChat calls isHiddenForCurrentUser, sees the HIDDEN preference for the current user, and shows the Join button. Once the server responds with the correct preferences, the button disappears.

App/src/libs/actions/Report/index.ts

Lines 1703 to 1714 in 829a2e5

	const newChat = buildOptimisticChatReport({
	participantList: participantAccountIDs,
	reportName: ReportActionsUtils.getReportActionText(parentReportAction),
	chatType: childReportChatType,
	policyID: parentReport?.policyID ?? CONST.POLICY.OWNER_EMAIL_FAKE,
	ownerAccountID: CONST.POLICY.OWNER_ACCOUNT_ID_FAKE,
	oldPolicyName: parentReport?.policyName ?? '',
	notificationPreference: getChildReportNotificationPreference(parentReportAction),
	parentReportActionID: parentReportAction.reportActionID,
	parentReportID: parentReport?.reportID,
	optimisticReportID: parentReportAction.childReportID,
	});

What changes do you think we should make in order to solve the problem?

The thread creator should always have their notification preference set to ALWAYS in the optimistic report, regardless of who authored the parent message. After buildOptimisticChatReport constructs the report, we should override the current user's participant entry to use ALWAYS. This way isHiddenForCurrentUser returns false immediately and the Join button never appears.

     const newChat = buildOptimisticChatReport({
         participantList: participantAccountIDs,
         reportName: ReportActionsUtils.getReportActionText(parentReportAction),
         chatType: childReportChatType,
         policyID: parentReport?.policyID ?? CONST.POLICY.OWNER_EMAIL_FAKE,
         ownerAccountID: CONST.POLICY.OWNER_ACCOUNT_ID_FAKE,
         oldPolicyName: parentReport?.policyName ?? '',
         notificationPreference: getChildReportNotificationPreference(parentReportAction),
         parentReportActionID: parentReportAction.reportActionID,
         parentReportID: parentReport?.reportID,
         optimisticReportID: parentReportAction.childReportID,
     });

+    // The thread creator should never see the Join button, so ensure their
+    // notification preference is ALWAYS regardless of who authored the parent message.
+    if (newChat.participants && deprecatedCurrentUserAccountID && newChat.participants[deprecatedCurrentUserAccountID]) {
+        newChat.participants[deprecatedCurrentUserAccountID].notificationPreference = CONST.REPORT.NOTIFICATION_PREFERENCE.ALWAYS;
+    }
+
     const childReportID = childReport?.reportID ?? parentReportAction.childReportID;

What alternative solutions did you explore? (Optional)

N/A

[MelvinBot]

🚫 Duplicated proposal withdrawn by 🤖 ProposalPolice.

[lorretheboy]

Proposal

Please re-state the problem that we are trying to solve in this issue.

Thread - Join button appears briefly, when a user starts thread in a message from another user

What is the root cause of that problem?

When a user starts a thread on a message sent by another user, the createChildReport function was using getChildReportNotificationPreference(parentReportAction) to set the notification preference. This function returns:

• ALWAYS if the current user is the action creator
• HIDDEN if the current user is NOT the action creator
  Since the parent message was sent by another user, the notification preference was set to HIDDEN, which caused canJoinChat() to return true (via isHiddenForCurrentUser(report) === true), showing the Join button.
  

  App/src/libs/actions/Report/index.ts

  Lines 1699 to 1725 in 3235cb2

  	function createChildReport(childReport: OnyxEntry<Report>, parentReportAction: ReportAction, parentReport: OnyxEntry<Report>): Report {
  	const participantAccountIDs = [...new Set([deprecatedCurrentUserAccountID, Number(parentReportAction.actorAccountID)])];
  	// Threads from DMs and selfDMs don't have a chatType. All other threads inherit the chatType from their parent
  	const childReportChatType = parentReport && isSelfDM(parentReport) ? undefined : parentReport?.chatType;
  	const newChat = buildOptimisticChatReport({
  	participantList: participantAccountIDs,
  	reportName: ReportActionsUtils.getReportActionText(parentReportAction),
  	chatType: childReportChatType,
  	policyID: parentReport?.policyID ?? CONST.POLICY.OWNER_EMAIL_FAKE,
  	ownerAccountID: CONST.POLICY.OWNER_ACCOUNT_ID_FAKE,
  	oldPolicyName: parentReport?.policyName ?? '',
  	notificationPreference: getChildReportNotificationPreference(parentReportAction),
  	parentReportActionID: parentReportAction.reportActionID,
  	parentReportID: parentReport?.reportID,
  	optimisticReportID: parentReportAction.childReportID,
  	});
  	const childReportID = childReport?.reportID ?? parentReportAction.childReportID;
  	if (!childReportID) {
  	const participantLogins = PersonalDetailsUtils.getLoginsByAccountIDs(Object.keys(newChat.participants ?? {}).map(Number));
  	openReport(newChat.reportID, deprecatedIntroSelected, '', participantLogins, newChat, parentReportAction.reportActionID, undefined, undefined, undefined, true);
  	} else {
  	Onyx.merge(`${ONYXKEYS.COLLECTION.REPORT}${childReportID}`, newChat);
  	}
  	return newChat;
  	}

What changes do you think we should make in order to solve the problem?

When creating a new thread (when childReportID is undefined), we now always use ALWAYS notification preference because the user is actively starting the thread and should be automatically joined

--- a/src/libs/actions/Report/index.ts
+++ b/src/libs/actions/Report/index.ts
@@ -1700,6 +1700,11 @@ function createChildReport(childReport: OnyxEntry<Report>, parentReportAction: R
     const participantAccountIDs = [...new Set([deprecatedCurrentUserAccountID, Number(parentReportAction.actorAccountID)])];
     // Threads from DMs and selfDMs don't have a chatType. All other threads inherit the chatType from their parent
     const childReportChatType = parentReport && isSelfDM(parentReport) ? undefined : parentReport?.chatType;
+    const childReportID = childReport?.reportID ?? parentReportAction.childReportID;
+    // When creating a new thread (no childReportID exists), the user is actively starting the thread
+    // so they should be joined with ALWAYS notification preference. For existing threads, use the
+    // existing notification preference from the parent report action.
+    const notificationPreference = childReportID ? getChildReportNotificationPreference(parentReportAction) : CONST.REPORT.NOTIFICATION_PREFERENCE.ALWAYS;
     const newChat = buildOptimisticChatReport({
         participantList: participantAccountIDs,
         reportName: ReportActionsUtils.getReportActionText(parentReportAction),
@@ -1707,13 +1712,12 @@ function createChildReport(childReport: OnyxEntry<Report>, parentReportAction: R
         policyID: parentReport?.policyID ?? CONST.POLICY.OWNER_EMAIL_FAKE,
         ownerAccountID: CONST.POLICY.OWNER_ACCOUNT_ID_FAKE,
         oldPolicyName: parentReport?.policyName ?? '',
-        notificationPreference: getChildReportNotificationPreference(parentReportAction),
+        notificationPreference,
         parentReportActionID: parentReportAction.reportActionID,
         parentReportID: parentReport?.reportID,
         optimisticReportID: parentReportAction.childReportID,
     });
 
-    const childReportID = childReport?.reportID ?? parentReportAction.childReportID;
     if (!childReportID) {
         const participantLogins = PersonalDetailsUtils.getLoginsByAccountIDs(Object.keys(newChat.participants ?? {}).map(Number));
         openReport(newChat.reportID, deprecatedIntroSelected, '', participantLogins, newChat, parentReportAction.reportActionID, undefined, undefined, undefined, true);

What alternative solutions did you explore? (Optional)

Reminder: Please use plain English, be brief and avoid jargon. Feel free to use images, charts or pseudo-code if necessary. Do not post large multi-line diffs or write walls of text. Do not create PRs unless you have been hired for this job.

[github-actions]

⚠️ @MelvinBot Your proposal is a duplicate of an already existing proposal and has been automatically withdrawn to prevent spam. Please review the existing proposals before submitting a new one.

[annaweber830]

Proposal

Please re-state the problem that we are trying to solve in this issue.

When starting a new thread from someone else’s message, the app navigates to the new thread but briefly shows a Join button in the header before it disappears.

What is the root cause of that problem?

When the parent message was authored by someone else, we compute the optimistic thread’s notification preference based on the parent action author instead of the thread creator. getChildReportNotificationPreference() falls back to HIDDEN when the current user is not the action creator:

App/src/libs/ReportUtils.ts

Lines 2792 to 2810 in 480fd3d

	/**
	* Checks if the current user is the action's author
	*/
	function isActionCreator(reportAction: OnyxInputOrEntry<ReportAction> | Partial<ReportAction>): boolean {
	return reportAction?.actorAccountID === currentUserAccountID;
	}
	/**
	* Returns the notification preference of the action's child report if it exists.
	* Otherwise, calculates it based on the action's authorship.
	*/
	function getChildReportNotificationPreference(reportAction: OnyxInputOrEntry<ReportAction> | Partial<ReportAction>): NotificationPreference {
	const childReportNotificationPreference = reportAction?.childReportNotificationPreference ?? '';
	if (childReportNotificationPreference) {
	return childReportNotificationPreference;
	}
	return isActionCreator(reportAction) ? CONST.REPORT.NOTIFICATION_PREFERENCE.ALWAYS : CONST.REPORT.NOTIFICATION_PREFERENCE.HIDDEN;
	}

createChildReport() uses that value to create an optimistic thread report:

App/src/libs/actions/Report/index.ts

Lines 1699 to 1714 in 480fd3d

	function createChildReport(childReport: OnyxEntry<Report>, parentReportAction: ReportAction, parentReport: OnyxEntry<Report>): Report {
	const participantAccountIDs = [...new Set([deprecatedCurrentUserAccountID, Number(parentReportAction.actorAccountID)])];
	// Threads from DMs and selfDMs don't have a chatType. All other threads inherit the chatType from their parent
	const childReportChatType = parentReport && isSelfDM(parentReport) ? undefined : parentReport?.chatType;
	const newChat = buildOptimisticChatReport({
	participantList: participantAccountIDs,
	reportName: ReportActionsUtils.getReportActionText(parentReportAction),
	chatType: childReportChatType,
	policyID: parentReport?.policyID ?? CONST.POLICY.OWNER_EMAIL_FAKE,
	ownerAccountID: CONST.POLICY.OWNER_ACCOUNT_ID_FAKE,
	oldPolicyName: parentReport?.policyName ?? '',
	notificationPreference: getChildReportNotificationPreference(parentReportAction),
	parentReportActionID: parentReportAction.reportActionID,
	parentReportID: parentReport?.reportID,
	optimisticReportID: parentReportAction.childReportID,
	});

But buildOptimisticChatReport() applies the passed notificationPreference to every participant (including the current user):

App/src/libs/ReportUtils.ts

Lines 7730 to 7758 in 480fd3d

	function buildOptimisticChatReport({
	participantList,
	reportName = CONST.REPORT.DEFAULT_REPORT_NAME,
	chatType,
	policyID = CONST.POLICY.OWNER_EMAIL_FAKE,
	ownerAccountID = CONST.REPORT.OWNER_ACCOUNT_ID_FAKE,
	isOwnPolicyExpenseChat = false,
	oldPolicyName = '',
	visibility,
	writeCapability,
	notificationPreference = CONST.REPORT.NOTIFICATION_PREFERENCE.ALWAYS,
	parentReportActionID = '',
	parentReportID = undefined,
	description = '',
	avatarUrl = '',
	optimisticReportID = '',
	isPinned = false,
	chatReportID = undefined,
	}: BuildOptimisticChatReportParams): OptimisticChatReport {
	const isWorkspaceChatType = chatType && isWorkspaceChat(chatType);
	const participants = participantList.reduce((reportParticipants: Participants, accountID: number) => {
	const participant: ReportParticipant = {
	notificationPreference,
	...(!isWorkspaceChatType && {role: accountID === currentUserAccountID ? CONST.REPORT.ROLE.ADMIN : CONST.REPORT.ROLE.MEMBER}),
	};
	// eslint-disable-next-line no-param-reassign
	reportParticipants[accountID] = participant;
	return reportParticipants;
	}, {} as Participants);

So, for a newly-created thread where childReportNotificationPreference is still empty and the parent action author is someone else, the optimistic thread report ends up with the current user’s notificationPreference = HIDDEN. That makes ReportUtils.isHiddenForCurrentUser(report) true, which makes ReportUtils.canJoinChat(report, ...) return true for a thread report, and HeaderView renders the Join button until the server response updates the preferences.

What changes do you think we should make in order to solve the problem?

When we’re creating an optimistic thread report and the parent action doesn’t yet have a childReportNotificationPreference, we should default the optimistic thread’s notification preference to ALWAYS (so the thread creator is treated as joined immediately). If the action already contains childReportNotificationPreference (existing threads / server-known state), keep the current behavior so the Join button can still appear when appropriate.

App/src/libs/actions/Report/index.ts

Lines 1699 to 1725 in 480fd3d

	function createChildReport(childReport: OnyxEntry<Report>, parentReportAction: ReportAction, parentReport: OnyxEntry<Report>): Report {
	const participantAccountIDs = [...new Set([deprecatedCurrentUserAccountID, Number(parentReportAction.actorAccountID)])];
	// Threads from DMs and selfDMs don't have a chatType. All other threads inherit the chatType from their parent
	const childReportChatType = parentReport && isSelfDM(parentReport) ? undefined : parentReport?.chatType;
	const newChat = buildOptimisticChatReport({
	participantList: participantAccountIDs,
	reportName: ReportActionsUtils.getReportActionText(parentReportAction),
	chatType: childReportChatType,
	policyID: parentReport?.policyID ?? CONST.POLICY.OWNER_EMAIL_FAKE,
	ownerAccountID: CONST.POLICY.OWNER_ACCOUNT_ID_FAKE,
	oldPolicyName: parentReport?.policyName ?? '',
	notificationPreference: getChildReportNotificationPreference(parentReportAction),
	parentReportActionID: parentReportAction.reportActionID,
	parentReportID: parentReport?.reportID,
	optimisticReportID: parentReportAction.childReportID,
	});
	const childReportID = childReport?.reportID ?? parentReportAction.childReportID;
	if (!childReportID) {
	const participantLogins = PersonalDetailsUtils.getLoginsByAccountIDs(Object.keys(newChat.participants ?? {}).map(Number));
	openReport(newChat.reportID, deprecatedIntroSelected, '', participantLogins, newChat, parentReportAction.reportActionID, undefined, undefined, undefined, true);
	} else {
	Onyx.merge(`${ONYXKEYS.COLLECTION.REPORT}${childReportID}`, newChat);
	}
	return newChat;
	}

Current code:

function createChildReport(childReport: OnyxEntry<Report>, parentReportAction: ReportAction, parentReport: OnyxEntry<Report>): Report {
    const participantAccountIDs = [...new Set([deprecatedCurrentUserAccountID, Number(parentReportAction.actorAccountID)])];
    // Threads from DMs and selfDMs don't have a chatType. All other threads inherit the chatType from their parent
    const childReportChatType = parentReport && isSelfDM(parentReport) ? undefined : parentReport?.chatType;
    const newChat = buildOptimisticChatReport({
        participantList: participantAccountIDs,
        reportName: ReportActionsUtils.getReportActionText(parentReportAction),
        chatType: childReportChatType,
        policyID: parentReport?.policyID ?? CONST.POLICY.OWNER_EMAIL_FAKE,
        ownerAccountID: CONST.POLICY.OWNER_ACCOUNT_ID_FAKE,
        oldPolicyName: parentReport?.policyName ?? '',
        notificationPreference: getChildReportNotificationPreference(parentReportAction),
        parentReportActionID: parentReportAction.reportActionID,
        parentReportID: parentReport?.reportID,
        optimisticReportID: parentReportAction.childReportID,
    });

    const childReportID = childReport?.reportID ?? parentReportAction.childReportID;
    if (!childReportID) {
        const participantLogins = PersonalDetailsUtils.getLoginsByAccountIDs(Object.keys(newChat.participants ?? {}).map(Number));
        openReport(newChat.reportID, deprecatedIntroSelected, '', participantLogins, newChat, parentReportAction.reportActionID, undefined, undefined, undefined, true);
    } else {
        Onyx.merge(`${ONYXKEYS.COLLECTION.REPORT}${childReportID}`, newChat);
    }

    return newChat;
}

Updated code:

function createChildReport(childReport: OnyxEntry<Report>, parentReportAction: ReportAction, parentReport: OnyxEntry<Report>): Report {
    const participantAccountIDs = [...new Set([deprecatedCurrentUserAccountID, Number(parentReportAction.actorAccountID)])];
    // Threads from DMs and selfDMs don't have a chatType. All other threads inherit the chatType from their parent
    const childReportChatType = parentReport && isSelfDM(parentReport) ? undefined : parentReport?.chatType;
    const notificationPreference = parentReportAction.childReportNotificationPreference
        ? getChildReportNotificationPreference(parentReportAction)
        : CONST.REPORT.NOTIFICATION_PREFERENCE.ALWAYS;
    const newChat = buildOptimisticChatReport({
        participantList: participantAccountIDs,
        reportName: ReportActionsUtils.getReportActionText(parentReportAction),
        chatType: childReportChatType,
        policyID: parentReport?.policyID ?? CONST.POLICY.OWNER_EMAIL_FAKE,
        ownerAccountID: CONST.POLICY.OWNER_ACCOUNT_ID_FAKE,
        oldPolicyName: parentReport?.policyName ?? '',
        notificationPreference,
        parentReportActionID: parentReportAction.reportActionID,
        parentReportID: parentReport?.reportID,
        optimisticReportID: parentReportAction.childReportID,
    });

    const childReportID = childReport?.reportID ?? parentReportAction.childReportID;
    if (!childReportID) {
        const participantLogins = PersonalDetailsUtils.getLoginsByAccountIDs(Object.keys(newChat.participants ?? {}).map(Number));
        openReport(newChat.reportID, deprecatedIntroSelected, '', participantLogins, newChat, parentReportAction.reportActionID, undefined, undefined, undefined, true);
    } else {
        Onyx.merge(`${ONYXKEYS.COLLECTION.REPORT}${childReportID}`, newChat);
    }

    return newChat;
}

What alternative solutions did you explore? (Optional)

• Overriding only the current user’s participant entry after building the optimistic report, but this requires special-casing participant mutation and still leaves the optimistic report default as HIDDEN for all other participants.
• Forcing ALWAYS inside getChildReportNotificationPreference()’s fallback path, but that risks changing behavior in other call sites that intentionally want HIDDEN when opening existing threads without an explicit childReportNotificationPreference.