diff --git a/src/libs/ReportUtils.js b/src/libs/ReportUtils.js
index e8ef18a3ca27..ad2b38707c7d 100644
--- a/src/libs/ReportUtils.js
+++ b/src/libs/ReportUtils.js
@@ -2352,6 +2352,7 @@ function shouldReportBeInOptionList(report, currentReportId, isInGSDMode, iouRep
     if (
         !report ||
         !report.reportID ||
+        report.isHidden ||
         (_.isEmpty(report.participantAccountIDs) && !isChatThread(report) && !isPublicRoom(report) && !isArchivedRoom(report) && !isMoneyRequestReport(report) && !isTaskReport(report))
     ) {
         return false;
@@ -2903,6 +2904,123 @@ function shouldDisableRename(report, policy) {
     return !_.keys(loginList).includes(policy.owner) && policy.role !== CONST.POLICY.ROLE.ADMIN;
 }
 
+/**
+ * Returns the onyx data needed for the task assignee chat
+ * @param {Number} accountID
+ * @param {String} assigneeEmail
+ * @param {Number} assigneeAccountID
+ * @param {String} taskReportID
+ * @param {String} assigneeChatReportID
+ * @param {String} parentReportID
+ * @param {String} title
+ * @param {Object} assigneeChatReport
+ * @returns {Object}
+ */
+function getTaskAssigneeChatOnyxData(accountID, assigneeEmail, assigneeAccountID, taskReportID, assigneeChatReportID, parentReportID, title, assigneeChatReport) {
+    // Set if we need to add a comment to the assignee chat notifying them that they have been assigned a task
+    let optimisticAssigneeAddComment;
+    // Set if this is a new chat that needs to be created for the assignee
+    let optimisticChatCreatedReportAction;
+    const currentTime = DateUtils.getDBTime();
+    const optimisticData = [];
+    const successData = [];
+    const failureData = [];
+
+    // You're able to assign a task to someone you haven't chatted with before - so we need to optimistically create the chat and the chat reportActions
+    // Only add the assignee chat report to onyx if we haven't already set it optimistically
+    if (assigneeChatReport.isOptimisticReport && lodashGet(assigneeChatReport, 'pendingFields.createChat') !== CONST.RED_BRICK_ROAD_PENDING_ACTION.ADD) {
+        optimisticChatCreatedReportAction = buildOptimisticCreatedReportAction(assigneeChatReportID);
+        optimisticData.push(
+            {
+                onyxMethod: Onyx.METHOD.MERGE,
+                key: `${ONYXKEYS.COLLECTION.REPORT}${assigneeChatReportID}`,
+                value: {
+                    pendingFields: {
+                        createChat: CONST.RED_BRICK_ROAD_PENDING_ACTION.ADD,
+                    },
+                    isHidden: false,
+                },
+            },
+            {
+                onyxMethod: Onyx.METHOD.MERGE,
+                key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${assigneeChatReportID}`,
+                value: {[optimisticChatCreatedReportAction.reportActionID]: optimisticChatCreatedReportAction},
+            },
+        );
+
+        successData.push({
+            onyxMethod: Onyx.METHOD.MERGE,
+            key: `${ONYXKEYS.COLLECTION.REPORT}${assigneeChatReportID}`,
+            value: {
+                pendingFields: {
+                    createChat: null,
+                },
+                isOptimisticReport: false,
+            },
+        });
+
+        failureData.push(
+            {
+                onyxMethod: Onyx.METHOD.SET,
+                key: `${ONYXKEYS.COLLECTION.REPORT}${assigneeChatReportID}`,
+                value: null,
+            },
+            {
+                onyxMethod: Onyx.METHOD.MERGE,
+                key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${assigneeChatReportID}`,
+                value: {[optimisticChatCreatedReportAction.reportActionID]: {pendingAction: null}},
+            },
+            // If we failed, we want to remove the optimistic personal details as it was likely due to an invalid login
+            {
+                onyxMethod: Onyx.METHOD.MERGE,
+                key: ONYXKEYS.PERSONAL_DETAILS_LIST,
+                value: {
+                    [assigneeAccountID]: null,
+                },
+            },
+        );
+    }
+
+    // If you're choosing to share the task in the same DM as the assignee then we don't need to create another reportAction indicating that you've been assigned
+    if (assigneeChatReportID !== parentReportID) {
+        optimisticAssigneeAddComment = buildOptimisticTaskCommentReportAction(taskReportID, title, assigneeEmail, assigneeAccountID, `Assigned a task to you: ${title}`, parentReportID);
+
+        const lastAssigneeCommentText = formatReportLastMessageText(optimisticAssigneeAddComment.reportAction.message[0].text);
+        const optimisticAssigneeReport = {
+            lastVisibleActionCreated: currentTime,
+            lastMessageText: lastAssigneeCommentText,
+            lastActorAccountID: accountID,
+            lastReadTime: currentTime,
+        };
+
+        optimisticData.push(
+            {
+                onyxMethod: Onyx.METHOD.MERGE,
+                key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${assigneeChatReportID}`,
+                value: {[optimisticAssigneeAddComment.reportAction.reportActionID]: optimisticAssigneeAddComment.reportAction},
+            },
+            {
+                onyxMethod: Onyx.METHOD.MERGE,
+                key: `${ONYXKEYS.COLLECTION.REPORT}${assigneeChatReportID}`,
+                value: optimisticAssigneeReport,
+            },
+        );
+        failureData.push({
+            onyxMethod: Onyx.METHOD.MERGE,
+            key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${assigneeChatReportID}`,
+            value: {[optimisticAssigneeAddComment.reportAction.reportActionID]: {pendingAction: null}},
+        });
+    }
+
+    return {
+        optimisticData,
+        successData,
+        failureData,
+        optimisticAssigneeAddComment,
+        optimisticChatCreatedReportAction,
+    };
+}
+
 export {
     getReportParticipantsTitle,
     isReportMessageAttachment,
@@ -3024,4 +3142,5 @@ export {
     shouldDisableSettings,
     shouldDisableRename,
     hasSingleParticipant,
+    getTaskAssigneeChatOnyxData,
 };
diff --git a/src/libs/actions/Task.js b/src/libs/actions/Task.js
index eeef8f479d97..6227686b3f45 100644
--- a/src/libs/actions/Task.js
+++ b/src/libs/actions/Task.js
@@ -4,7 +4,6 @@ import _ from 'underscore';
 import ONYXKEYS from '../../ONYXKEYS';
 import * as API from '../API';
 import * as ReportUtils from '../ReportUtils';
-import * as Report from './Report';
 import Navigation from '../Navigation/Navigation';
 import ROUTES from '../../ROUTES';
 import CONST from '../../CONST';
@@ -25,6 +24,12 @@ Onyx.connect({
     },
 });
 
+let allPersonalDetails;
+Onyx.connect({
+    key: ONYXKEYS.PERSONAL_DETAILS_LIST,
+    callback: (val) => (allPersonalDetails = val),
+});
+
 /**
  * Clears out the task info from the store
  */
@@ -33,47 +38,42 @@ function clearOutTaskInfo() {
 }
 
 /**
- * Assign a task to a user
- * Function title is createTask for consistency with the rest of the actions
- * and also because we can create a task without assigning it to anyone
+ * A task needs two things to be created - a title and a parent report
+ * When you create a task report, there are a few things that happen:
+ * A task report is created, along with a CreatedReportAction for that new task report
+ * A reportAction indicating that a task was created is added to the parent report (share destination)
+ * If you assign the task to someone, a reportAction is created in the chat between you and the assignee to inform them of the task
+ *
+ * So you have the following optimistic items potentially being created:
+ * 1. The task report
+ * 1a. The CreatedReportAction for the task report
+ * 2. The TaskReportAction on the parent report
+ * 3. The chat report between you and the assignee
+ * 3a. The CreatedReportAction for the assignee chat report
+ * 3b. The TaskReportAction on the assignee chat report
+ *
  * @param {String} parentReportID
  * @param {String} title
  * @param {String} description
- * @param {String} assignee
+ * @param {String} assigneeEmail
  * @param {Number} assigneeAccountID
- *
+ * @param {Object} assigneeChatReport - The chat report between you and the assignee
  */
-
-function createTaskAndNavigate(parentReportID, title, description, assignee, assigneeAccountID = 0) {
-    // Create the task report
+function createTaskAndNavigate(parentReportID, title, description, assigneeEmail, assigneeAccountID = 0, assigneeChatReport = null) {
     const optimisticTaskReport = ReportUtils.buildOptimisticTaskReport(currentUserAccountID, assigneeAccountID, parentReportID, title, description);
 
-    // Grab the assigneeChatReportID if there is an assignee and if it's not the same as the parentReportID
-    // then we create an optimistic add comment report action on the assignee's chat to notify them of the task
-    const assigneeChatReportID = lodashGet(ReportUtils.getChatByParticipants([assigneeAccountID]), 'reportID');
+    const assigneeChatReportID = assigneeChatReport ? assigneeChatReport.reportID : 0;
     const taskReportID = optimisticTaskReport.reportID;
-    let optimisticAssigneeAddComment;
-    if (assigneeChatReportID && assigneeChatReportID !== parentReportID) {
-        optimisticAssigneeAddComment = ReportUtils.buildOptimisticTaskCommentReportAction(
-            taskReportID,
-            title,
-            assignee,
-            assigneeAccountID,
-            `Assigned a task to you: ${title}`,
-            parentReportID,
-        );
-    }
+    let assigneeChatReportOnyxData;
 
-    // Create the CreatedReportAction on the task
+    // Parent ReportAction indicating that a task has been created
     const optimisticTaskCreatedAction = ReportUtils.buildOptimisticCreatedReportAction(currentUserEmail);
-    const optimisticAddCommentReport = ReportUtils.buildOptimisticTaskCommentReportAction(taskReportID, title, assignee, assigneeAccountID, `Created a task: ${title}`, parentReportID);
+    const optimisticAddCommentReport = ReportUtils.buildOptimisticTaskCommentReportAction(taskReportID, title, assigneeEmail, assigneeAccountID, `Created a task: ${title}`, parentReportID);
     optimisticTaskReport.parentReportActionID = optimisticAddCommentReport.reportAction.reportActionID;
 
     const currentTime = DateUtils.getDBTime();
-
     const lastCommentText = ReportUtils.formatReportLastMessageText(optimisticAddCommentReport.reportAction.message[0].text);
-
-    const optimisticReport = {
+    const optimisticParentReport = {
         lastVisibleActionCreated: currentTime,
         lastMessageText: lastCommentText,
         lastActorAccountID: currentUserAccountID,
@@ -81,6 +81,9 @@ function createTaskAndNavigate(parentReportID, title, description, assignee, ass
         lastMessageTranslationKey: '',
     };
 
+    // We're only setting onyx data for the task report here because it's possible for the parent report to not exist yet (if you're assigning a task to someone you haven't chatted with before)
+    // So we don't want to set the parent report data until we've successfully created that chat report
+    // FOR TASK REPORT
     const optimisticData = [
         {
             onyxMethod: Onyx.METHOD.SET,
@@ -101,18 +104,9 @@ function createTaskAndNavigate(parentReportID, title, description, assignee, ass
             key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${optimisticTaskReport.reportID}`,
             value: {[optimisticTaskCreatedAction.reportActionID]: optimisticTaskCreatedAction},
         },
-        {
-            onyxMethod: Onyx.METHOD.MERGE,
-            key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${parentReportID}`,
-            value: {[optimisticAddCommentReport.reportAction.reportActionID]: optimisticAddCommentReport.reportAction},
-        },
-        {
-            onyxMethod: Onyx.METHOD.MERGE,
-            key: `${ONYXKEYS.COLLECTION.REPORT}${parentReportID}`,
-            value: optimisticReport,
-        },
     ];
 
+    // FOR TASK REPORT
     const successData = [
         {
             onyxMethod: Onyx.METHOD.MERGE,
@@ -132,13 +126,9 @@ function createTaskAndNavigate(parentReportID, title, description, assignee, ass
             key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${optimisticTaskReport.reportID}`,
             value: {[optimisticTaskCreatedAction.reportActionID]: {pendingAction: null}},
         },
-        {
-            onyxMethod: Onyx.METHOD.MERGE,
-            key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${parentReportID}`,
-            value: {[optimisticAddCommentReport.reportAction.reportActionID]: {pendingAction: null}},
-        },
     ];
 
+    // FOR TASK REPORT
     const failureData = [
         {
             onyxMethod: Onyx.METHOD.SET,
@@ -150,48 +140,52 @@ function createTaskAndNavigate(parentReportID, title, description, assignee, ass
             key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${optimisticTaskReport.reportID}`,
             value: {[optimisticTaskCreatedAction.reportActionID]: {pendingAction: null}},
         },
-        {
-            onyxMethod: Onyx.METHOD.MERGE,
-            key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${parentReportID}`,
-            value: {[optimisticAddCommentReport.reportAction.reportActionID]: {pendingAction: null}},
-        },
     ];
 
-    if (optimisticAssigneeAddComment) {
-        const lastAssigneeCommentText = ReportUtils.formatReportLastMessageText(optimisticAssigneeAddComment.reportAction.message[0].text);
-
-        const optimisticAssigneeReport = {
-            lastVisibleActionCreated: currentTime,
-            lastMessageText: lastAssigneeCommentText,
-            lastActorAccountID: currentUserAccountID,
-            lastReadTime: currentTime,
-        };
-
-        optimisticData.push(
-            {
-                onyxMethod: Onyx.METHOD.MERGE,
-                key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${assigneeChatReportID}`,
-                value: {[optimisticAssigneeAddComment.reportAction.reportActionID]: optimisticAssigneeAddComment.reportAction},
-            },
-            {
-                onyxMethod: Onyx.METHOD.MERGE,
-                key: `${ONYXKEYS.COLLECTION.REPORT}${assigneeChatReportID}`,
-                value: optimisticAssigneeReport,
-            },
+    if (assigneeChatReport) {
+        assigneeChatReportOnyxData = ReportUtils.getTaskAssigneeChatOnyxData(
+            currentUserAccountID,
+            assigneeEmail,
+            assigneeAccountID,
+            taskReportID,
+            assigneeChatReportID,
+            parentReportID,
+            title,
+            assigneeChatReport,
         );
+        optimisticData.push(...assigneeChatReportOnyxData.optimisticData);
+        successData.push(...assigneeChatReportOnyxData.successData);
+        failureData.push(...assigneeChatReportOnyxData.failureData);
+    }
 
-        successData.push({
+    // Now that we've created the optimistic chat report and chat reportActions, we can update the parent report data
+    // FOR PARENT REPORT (SHARE DESTINATION)
+    optimisticData.push(
+        {
             onyxMethod: Onyx.METHOD.MERGE,
-            key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${assigneeChatReportID}`,
-            value: {[optimisticAssigneeAddComment.reportAction.reportActionID]: {pendingAction: null}},
-        });
-
-        failureData.push({
+            key: `${ONYXKEYS.COLLECTION.REPORT}${parentReportID}`,
+            value: optimisticParentReport,
+        },
+        {
             onyxMethod: Onyx.METHOD.MERGE,
-            key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${assigneeChatReportID}`,
-            value: {[optimisticAssigneeAddComment.reportAction.reportActionID]: {pendingAction: null}},
-        });
-    }
+            key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${parentReportID}`,
+            value: {[optimisticAddCommentReport.reportAction.reportActionID]: optimisticAddCommentReport.reportAction},
+        },
+    );
+
+    // FOR PARENT REPORT (SHARE DESTINATION)
+    successData.push({
+        onyxMethod: Onyx.METHOD.MERGE,
+        key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${parentReportID}`,
+        value: {[optimisticAddCommentReport.reportAction.reportActionID]: {pendingAction: null}},
+    });
+
+    // FOR PARENT REPORT (SHARE DESTINATION)
+    failureData.push({
+        onyxMethod: Onyx.METHOD.MERGE,
+        key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${parentReportID}`,
+        value: {[optimisticAddCommentReport.reportAction.reportActionID]: {pendingAction: null}},
+    });
 
     API.write(
         'CreateTask',
@@ -200,13 +194,17 @@ function createTaskAndNavigate(parentReportID, title, description, assignee, ass
             parentReportID,
             taskReportID: optimisticTaskReport.reportID,
             createdTaskReportActionID: optimisticTaskCreatedAction.reportActionID,
-            reportName: optimisticTaskReport.reportName,
             title: optimisticTaskReport.reportName,
             description: optimisticTaskReport.description,
-            assignee,
+            assignee: assigneeEmail,
             assigneeAccountID,
             assigneeChatReportID,
-            assigneeChatReportActionID: optimisticAssigneeAddComment ? optimisticAssigneeAddComment.reportAction.reportActionID : 0,
+            assigneeChatReportActionID:
+                assigneeChatReportOnyxData && assigneeChatReportOnyxData.optimisticAssigneeAddComment
+                    ? assigneeChatReportOnyxData.optimisticAssigneeAddComment.reportAction.reportActionID
+                    : 0,
+            assigneeChatCreatedReportActionID:
+                assigneeChatReportOnyxData && assigneeChatReportOnyxData.optimisticChatCreatedReportAction ? assigneeChatReportOnyxData.optimisticChatCreatedReportAction.reportActionID : 0,
         },
         {optimisticData, successData, failureData},
     );
@@ -401,12 +399,9 @@ function reopenTask(taskReport, taskTitle) {
  * @param {object} report
  * @param {Number} ownerAccountID
  * @param {Object} editedTask
- * @param {String} editedTask.title
- * @param {String} editedTask.description
- * @param {String} editedTask.assignee
- * @param {Number} editedTask.assigneeAccountID
+ * @param {Object} assigneeChatReport - The chat report between you and the assignee
  */
-function editTaskAndNavigate(report, ownerAccountID, {title, description, assignee = '', assigneeAccountID = 0}) {
+function editTaskAndNavigate(report, ownerAccountID, {title, description, assignee = '', assigneeAccountID = 0}, assigneeChatReport = null) {
     // Create the EditedReportAction on the task
     const editTaskReportAction = ReportUtils.buildOptimisticEditedTaskReportAction(currentUserEmail);
 
@@ -416,22 +411,8 @@ function editTaskAndNavigate(report, ownerAccountID, {title, description, assign
     // Description can be unset, so we default to an empty string if so
     const reportDescription = (!_.isUndefined(description) ? description : lodashGet(report, 'description', '')).trim();
 
-    // If we make a change to the assignee, we want to add a comment to the assignee's chat
-    let optimisticAssigneeAddComment;
-    let assigneeChatReportID;
-    if (assigneeAccountID && assigneeAccountID !== report.managerID && assigneeAccountID !== ownerAccountID) {
-        assigneeChatReportID = lodashGet(ReportUtils.getChatByParticipants([assigneeAccountID]), ['reportID'], undefined);
-
-        if (assigneeChatReportID && assigneeChatReportID !== report.parentReportID.toString()) {
-            optimisticAssigneeAddComment = ReportUtils.buildOptimisticTaskCommentReportAction(
-                report.reportID,
-                reportName,
-                assignee,
-                assigneeAccountID,
-                `Assigned a task to you: ${reportName}`,
-            );
-        }
-    }
+    let assigneeChatReportOnyxData;
+    const assigneeChatReportID = assigneeChatReport ? assigneeChatReport.reportID : 0;
 
     const optimisticData = [
         {
@@ -486,35 +467,22 @@ function editTaskAndNavigate(report, ownerAccountID, {title, description, assign
         },
     ];
 
-    if (optimisticAssigneeAddComment) {
-        const currentTime = DateUtils.getDBTime();
-        const lastAssigneeCommentText = ReportUtils.formatReportLastMessageText(optimisticAssigneeAddComment.reportAction.message[0].text);
-
-        const optimisticAssigneeReport = {
-            lastVisibleActionCreated: currentTime,
-            lastMessageText: lastAssigneeCommentText,
-            lastActorAccountID: ownerAccountID,
-            lastReadTime: currentTime,
-        };
-
-        optimisticData.push(
-            {
-                onyxMethod: Onyx.METHOD.MERGE,
-                key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${assigneeChatReportID}`,
-                value: {[optimisticAssigneeAddComment.reportAction.reportActionID]: optimisticAssigneeAddComment.reportAction},
-            },
-            {
-                onyxMethod: Onyx.METHOD.MERGE,
-                key: `${ONYXKEYS.COLLECTION.REPORT}${assigneeChatReportID}`,
-                value: optimisticAssigneeReport,
-            },
+    // If we make a change to the assignee, we want to add a comment to the assignee's chat
+    // Check if the assignee actually changed
+    if (assigneeAccountID && assigneeAccountID !== report.managerID && assigneeAccountID !== ownerAccountID && assigneeChatReport) {
+        assigneeChatReportOnyxData = ReportUtils.getTaskAssigneeChatOnyxData(
+            currentUserAccountID,
+            assignee,
+            assigneeAccountID,
+            report.reportID,
+            assigneeChatReportID,
+            report.parentReportID,
+            reportName,
+            assigneeChatReport,
         );
-
-        failureData.push({
-            onyxMethod: Onyx.METHOD.MERGE,
-            key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${assigneeChatReportID}`,
-            value: {[optimisticAssigneeAddComment.reportAction.reportActionID]: {pendingAction: null}},
-        });
+        optimisticData.push(...assigneeChatReportOnyxData.optimisticData);
+        successData.push(...assigneeChatReportOnyxData.successData);
+        failureData.push(...assigneeChatReportOnyxData.failureData);
     }
 
     API.write(
@@ -526,7 +494,90 @@ function editTaskAndNavigate(report, ownerAccountID, {title, description, assign
             assignee: assignee || report.managerEmail,
             assigneeAccountID: assigneeAccountID || report.managerID,
             editedTaskReportActionID: editTaskReportAction.reportActionID,
-            assigneeChatReportActionID: optimisticAssigneeAddComment ? optimisticAssigneeAddComment.reportAction.reportActionID : 0,
+            assigneeChatReportID,
+            assigneeChatReportActionID:
+                assigneeChatReportOnyxData && assigneeChatReportOnyxData.optimisticAssigneeAddComment
+                    ? assigneeChatReportOnyxData.optimisticAssigneeAddComment.reportAction.reportActionID
+                    : 0,
+            assigneeChatCreatedReportActionID:
+                assigneeChatReportOnyxData && assigneeChatReportOnyxData.optimisticChatCreatedReportAction ? assigneeChatReportOnyxData.optimisticChatCreatedReportAction.reportActionID : 0,
+        },
+        {optimisticData, successData, failureData},
+    );
+
+    Navigation.dismissModal(report.reportID);
+}
+
+function editTaskAssigneeAndNavigate(report, ownerAccountID, assigneeEmail, assigneeAccountID = 0, assigneeChatReport = null) {
+    // Create the EditedReportAction on the task
+    const editTaskReportAction = ReportUtils.buildOptimisticEditedTaskReportAction(currentUserEmail);
+    const reportName = report.reportName.trim();
+
+    let assigneeChatReportOnyxData;
+    const assigneeChatReportID = assigneeChatReport ? assigneeChatReport.reportID : 0;
+
+    const optimisticData = [
+        {
+            onyxMethod: Onyx.METHOD.MERGE,
+            key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${report.reportID}`,
+            value: {[editTaskReportAction.reportActionID]: editTaskReportAction},
+        },
+        {
+            onyxMethod: Onyx.METHOD.MERGE,
+            key: `${ONYXKEYS.COLLECTION.REPORT}${report.reportID}`,
+            value: {
+                reportName,
+                managerID: assigneeAccountID || report.managerID,
+                managerEmail: assigneeEmail || report.managerEmail,
+            },
+        },
+    ];
+    const successData = [];
+    const failureData = [
+        {
+            onyxMethod: Onyx.METHOD.MERGE,
+            key: `${ONYXKEYS.COLLECTION.REPORT_ACTIONS}${report.reportID}`,
+            value: {[editTaskReportAction.reportActionID]: {pendingAction: null}},
+        },
+        {
+            onyxMethod: Onyx.METHOD.MERGE,
+            key: `${ONYXKEYS.COLLECTION.REPORT}${report.reportID}`,
+            value: {assignee: report.managerEmail, assigneeAccountID: report.managerID},
+        },
+    ];
+
+    // If we make a change to the assignee, we want to add a comment to the assignee's chat
+    // Check if the assignee actually changed
+    if (assigneeAccountID && assigneeAccountID !== report.managerID && assigneeAccountID !== ownerAccountID && assigneeChatReport) {
+        assigneeChatReportOnyxData = ReportUtils.getTaskAssigneeChatOnyxData(
+            currentUserAccountID,
+            assigneeEmail,
+            assigneeAccountID,
+            report.reportID,
+            assigneeChatReportID,
+            report.parentReportID,
+            reportName,
+            assigneeChatReport,
+        );
+        optimisticData.push(...assigneeChatReportOnyxData.optimisticData);
+        successData.push(...assigneeChatReportOnyxData.successData);
+        failureData.push(...assigneeChatReportOnyxData.failureData);
+    }
+
+    API.write(
+        'EditTaskAssignee',
+        {
+            taskReportID: report.reportID,
+            assignee: assigneeEmail || report.managerEmail,
+            assigneeAccountID: assigneeAccountID || report.managerID,
+            editedTaskReportActionID: editTaskReportAction.reportActionID,
+            assigneeChatReportID,
+            assigneeChatReportActionID:
+                assigneeChatReportOnyxData && assigneeChatReportOnyxData.optimisticAssigneeAddComment
+                    ? assigneeChatReportOnyxData.optimisticAssigneeAddComment.reportAction.reportActionID
+                    : 0,
+            assigneeChatCreatedReportActionID:
+                assigneeChatReportOnyxData && assigneeChatReportOnyxData.optimisticChatCreatedReportAction ? assigneeChatReportOnyxData.optimisticChatCreatedReportAction.reportActionID : 0,
         },
         {optimisticData, successData, failureData},
     );
@@ -578,40 +629,65 @@ function setShareDestinationValue(shareDestination) {
     Onyx.merge(ONYXKEYS.TASK, {shareDestination});
 }
 
+/* Sets the assigneeChatReport details for the task
+ * @param {Object} chatReport
+ */
+function setAssigneeChatReport(chatReport) {
+    Onyx.merge(ONYXKEYS.TASK, {assigneeChatReport: chatReport});
+}
+
 /**
  * Sets the assignee value for the task and checks for an existing chat with the assignee
  * If there is no existing chat, it creates an optimistic chat report
  * It also sets the shareDestination as that chat report if a share destination isn't already set
- * @param {string} assignee
+ * @param {string} assigneeEmail
  * @param {Number} assigneeAccountID
  * @param {string} shareDestination
  * @param {boolean} isCurrentUser
  */
 
-function setAssigneeValue(assignee, assigneeAccountID, shareDestination, isCurrentUser = false) {
-    let newAssigneeAccountID = Number(assigneeAccountID);
+function setAssigneeValue(assigneeEmail, assigneeAccountID, shareDestination, isCurrentUser = false) {
+    let chatReport;
 
-    // Generate optimistic accountID if this is a brand new user account that hasn't been created yet
-    if (!newAssigneeAccountID) {
-        newAssigneeAccountID = UserUtils.generateAccountID(assignee);
-    }
     if (!isCurrentUser) {
-        let newChat = {};
-        const chat = ReportUtils.getChatByParticipants([newAssigneeAccountID]);
-        if (!chat) {
-            newChat = ReportUtils.buildOptimisticChatReport([newAssigneeAccountID]);
+        chatReport = ReportUtils.getChatByParticipantsByLoginList([assigneeEmail]) || ReportUtils.getChatByParticipants([assigneeAccountID]);
+        if (!chatReport) {
+            chatReport = ReportUtils.buildOptimisticChatReport([assigneeAccountID]);
+            chatReport.isOptimisticReport = true;
+
+            // When assigning a task to a new user, by default we share the task in their DM
+            // However, the DM doesn't exist yet - and will be created optimistically once the task is created
+            // We don't want to show the new DM yet, because if you select an assignee and then change the assignee, the previous DM will still be shown
+            // So here, we create it optimistically to share it with the assignee, but we have to hide it until the task is created
+            chatReport.isHidden = true;
+            Onyx.set(`${ONYXKEYS.COLLECTION.REPORT}${chatReport.reportID}`, chatReport);
+
+            // If this is an optimistic report, we likely don't have their personal details yet so we set it here optimistically as well
+            const optimisticPersonalDetailsListAction = {
+                accountID: assigneeAccountID,
+                avatar: lodashGet(allPersonalDetails, [assigneeAccountID, 'avatar'], UserUtils.getDefaultAvatarURL(assigneeAccountID)),
+                displayName: lodashGet(allPersonalDetails, [assigneeAccountID, 'displayName'], assigneeEmail),
+                login: assigneeEmail,
+            };
+            Onyx.merge(ONYXKEYS.PERSONAL_DETAILS_LIST, {[assigneeAccountID]: optimisticPersonalDetailsListAction});
         }
-        const reportID = chat ? chat.reportID : newChat.reportID;
 
+        setAssigneeChatReport(chatReport);
+
+        // If there is no share destination set, automatically set it to the assignee chat report
+        // This allows for a much quicker process when creating a new task and is likely the desired share destination most times
         if (!shareDestination) {
-            setShareDestinationValue(reportID);
+            setShareDestinationValue(chatReport.reportID);
         }
-
-        Report.openReport(reportID, [assignee], newChat);
     }
 
     // This is only needed for creation of a new task and so it should only be stored locally
-    Onyx.merge(ONYXKEYS.TASK, {assignee, assigneeAccountID: newAssigneeAccountID});
+    Onyx.merge(ONYXKEYS.TASK, {assignee: assigneeEmail, assigneeAccountID});
+
+    // When we're editing the assignee, we immediately call EditTaskAndNavigate. Since setting the assignee is async,
+    // the chatReport is not yet set when EditTaskAndNavigate is called. So we return the chatReport here so that
+    // EditTaskAndNavigate can use it.
+    return chatReport;
 }
 
 /**
@@ -818,6 +894,7 @@ function clearEditTaskErrors(reportID) {
 export {
     createTaskAndNavigate,
     editTaskAndNavigate,
+    editTaskAssigneeAndNavigate,
     setTitleValue,
     setDescriptionValue,
     setTaskReport,
diff --git a/src/pages/home/sidebar/SidebarLinksData.js b/src/pages/home/sidebar/SidebarLinksData.js
index 58a7e676403a..6f5f96e2a050 100644
--- a/src/pages/home/sidebar/SidebarLinksData.js
+++ b/src/pages/home/sidebar/SidebarLinksData.js
@@ -114,6 +114,7 @@ const chatReportSelector = (report) =>
         participantAccountIDs: report.participantAccountIDs,
         hasDraft: report.hasDraft,
         isPinned: report.isPinned,
+        isHidden: report.isHidden,
         errorFields: {
             addWorkspaceRoom: report.errorFields && report.errorFields.addWorkspaceRoom,
         },
diff --git a/src/pages/tasks/NewTaskPage.js b/src/pages/tasks/NewTaskPage.js
index 4b1aa0c0101b..4c915db567c4 100644
--- a/src/pages/tasks/NewTaskPage.js
+++ b/src/pages/tasks/NewTaskPage.js
@@ -126,7 +126,7 @@ function NewTaskPage(props) {
         }
 
         shouldClearOutTaskInfoOnUnmount.current = true;
-        Task.createTaskAndNavigate(parentReport.reportID, props.task.title, props.task.description, props.task.assignee, props.task.assigneeAccountID);
+        Task.createTaskAndNavigate(parentReport.reportID, props.task.title, props.task.description, props.task.assignee, props.task.assigneeAccountID, props.task.assigneeChatReport);
     }
 
     if (!Permissions.canUseTasks(props.betas)) {
diff --git a/src/pages/tasks/TaskAssigneeSelectorModal.js b/src/pages/tasks/TaskAssigneeSelectorModal.js
index 784c4c1a14df..245d00f3d0f7 100644
--- a/src/pages/tasks/TaskAssigneeSelectorModal.js
+++ b/src/pages/tasks/TaskAssigneeSelectorModal.js
@@ -172,15 +172,10 @@ function TaskAssigneeSelectorModal(props) {
 
         // Check to see if we're editing a task and if so, update the assignee
         if (report) {
-            // There was an issue where sometimes a new assignee didn't have a DM thread
-            // This would cause the app to crash, so we need to make sure we have a DM thread
-            Task.setAssigneeValue(option.login, option.accountID, props.route.params.reportID, OptionsListUtils.isCurrentUser(option));
+            const assigneeChatReport = Task.setAssigneeValue(option.login, option.accountID, props.route.params.reportID, OptionsListUtils.isCurrentUser(option));
 
             // Pass through the selected assignee
-            Task.editTaskAndNavigate(report, props.session.accountID, {
-                assignee: option.login,
-                assigneeAccountID: option.accountID,
-            });
+            Task.editTaskAssigneeAndNavigate(props.task.report, props.session.accountID, option.login, option.accountID, assigneeChatReport);
         }
     };