diff --git a/app/api/server/v1/channels.js b/app/api/server/v1/channels.js
index 4ac353773690c..ac01010839101 100644
--- a/app/api/server/v1/channels.js
+++ b/app/api/server/v1/channels.js
@@ -18,12 +18,7 @@ function findChannelByIdOrName({ params, checkedArchived = true, userId }) {
 
 	const fields = { ...API.v1.defaultFieldsToExclude };
 
-	let room;
-	if (params.roomId) {
-		room = Rooms.findOneById(params.roomId, { fields });
-	} else if (params.roomName) {
-		room = Rooms.findOneByName(params.roomName, { fields });
-	}
+	const room = Rooms.findOneByIdOrName(params.roomId || params.roomName, { fields });
 
 	if (!room || (room.t !== 'c' && room.t !== 'l')) {
 		throw new Meteor.Error('error-room-not-found', 'The required "roomId" or "roomName" param provided does not match any channel');
@@ -338,17 +333,7 @@ API.v1.addRoute('channels.history', { authRequired: true }, {
 	get() {
 		const findResult = findChannelByIdOrName({ params: this.requestParams(), checkedArchived: false });
 
-		let latestDate;
-		if (this.queryParams.latest) {
-			latestDate = new Date(this.queryParams.latest);
-		}
-
-		let oldestDate;
-		if (this.queryParams.oldest) {
-			oldestDate = new Date(this.queryParams.oldest);
-		}
-
-		const inclusive = this.queryParams.inclusive || false;
+		const { oldest, latest, inclusive, unreads } = this.queryParams;
 
 		let count = 20;
 		if (this.queryParams.count) {
@@ -360,18 +345,21 @@ API.v1.addRoute('channels.history', { authRequired: true }, {
 			offset = parseInt(this.queryParams.offset);
 		}
 
-		const unreads = this.queryParams.unreads || false;
+		const excludeTypes = findResult.sysMes || [];
+
+		console.log(excludeTypes);
 
 		let result;
 		Meteor.runAsUser(this.userId, () => {
 			result = Meteor.call('getChannelHistory', {
 				rid: findResult._id,
-				latest: latestDate,
-				oldest: oldestDate,
+				latest,
+				oldest,
 				inclusive,
 				offset,
 				count,
 				unreads,
+				excludeTypes,
 			});
 		});
 
diff --git a/app/api/server/v1/chat.js b/app/api/server/v1/chat.js
index 52bb679846ef9..7224c0a8e0ee7 100644
--- a/app/api/server/v1/chat.js
+++ b/app/api/server/v1/chat.js
@@ -129,6 +129,12 @@ API.v1.addRoute('chat.pinMessage', { authRequired: true }, {
 
 API.v1.addRoute('chat.postMessage', { authRequired: true }, {
 	post() {
+		const { alias, avatar } = this.bodyParams;
+
+		if ((alias || avatar) && !hasPermission(this.userId, 'message-impersonate')) {
+			return API.v1.failure('Unauthorized. You must have the permission "message-impersonate" to use custom alias and avatar.');
+		}
+
 		const messageReturn = processWebhookMessage(this.bodyParams, this.user)[0];
 
 		if (!messageReturn) {
@@ -176,6 +182,12 @@ API.v1.addRoute('chat.sendMessage', { authRequired: true }, {
 			throw new Meteor.Error('error-invalid-params', 'The "message" parameter must be provided.');
 		}
 
+		const { alias, avatar } = this.bodyParams;
+
+		if ((alias || avatar) && !hasPermission('message-impersonate')) {
+			return API.v1.failure('Unauthorized. You must have the permission "message-impersonate" to use custom alias and avatar.');
+		}
+
 		const sent = executeSendMessage(this.userId, this.bodyParams.message);
 		const [message] = normalizeMessagesForUser([sent], this.userId);
 
diff --git a/app/api/server/v1/groups.js b/app/api/server/v1/groups.js
index 9d2c4e5a8f92f..0b9510979658d 100644
--- a/app/api/server/v1/groups.js
+++ b/app/api/server/v1/groups.js
@@ -328,17 +328,7 @@ API.v1.addRoute('groups.history', { authRequired: true }, {
 	get() {
 		const findResult = findPrivateGroupByIdOrName({ params: this.requestParams(), userId: this.userId, checkedArchived: false });
 
-		let latestDate = new Date();
-		if (this.queryParams.latest) {
-			latestDate = new Date(this.queryParams.latest);
-		}
-
-		let oldestDate = undefined;
-		if (this.queryParams.oldest) {
-			oldestDate = new Date(this.queryParams.oldest);
-		}
-
-		const inclusive = this.queryParams.inclusive || false;
+		const { oldest, latest, inclusive, unreads } = this.queryParams;
 
 		let count = 20;
 		if (this.queryParams.count) {
@@ -350,11 +340,20 @@ API.v1.addRoute('groups.history', { authRequired: true }, {
 			offset = parseInt(this.queryParams.offset);
 		}
 
-		const unreads = this.queryParams.unreads || false;
+		const excludeTypes = findResult.sysMes || [];
 
 		let result;
 		Meteor.runAsUser(this.userId, () => {
-			result = Meteor.call('getChannelHistory', { rid: findResult.rid, latest: latestDate, oldest: oldestDate, inclusive, offset, count, unreads });
+			result = Meteor.call('getChannelHistory', {
+				rid: findResult.rid,
+				latest,
+				oldest,
+				inclusive,
+				offset,
+				count,
+				unreads,
+				excludeTypes,
+			});
 		});
 
 		if (!result) {
diff --git a/app/api/server/v1/invites.js b/app/api/server/v1/invites.js
index 9409458e3093a..49fccbcfb0cca 100644
--- a/app/api/server/v1/invites.js
+++ b/app/api/server/v1/invites.js
@@ -46,7 +46,7 @@ API.v1.addRoute('validateInviteToken', { authRequired: false }, {
 	post() {
 		const { token } = this.bodyParams;
 
-		if (!token) {
+		if (!token || typeof token !== 'string') {
 			throw new Meteor.Error('error-invalid-token', 'The invite token is invalid.', { method: 'validateInviteToken', field: 'token' });
 		}
 
diff --git a/app/authorization/server/startup.js b/app/authorization/server/startup.js
index 7d5efbdca1679..76cea6a8a396a 100644
--- a/app/authorization/server/startup.js
+++ b/app/authorization/server/startup.js
@@ -63,6 +63,7 @@ Meteor.startup(function() {
 		{ _id: 'manage-selected-settings', 	         roles: ['admin'] },
 		{ _id: 'mention-all',                        roles: ['admin', 'owner', 'moderator', 'user'] },
 		{ _id: 'mention-here',                       roles: ['admin', 'owner', 'moderator', 'user'] },
+		{ _id: 'message-impersonate', roles: ['bot'] },
 		{ _id: 'mute-user',                          roles: ['admin', 'owner', 'moderator'] },
 		{ _id: 'remove-user',                        roles: ['admin', 'owner', 'moderator'] },
 		{ _id: 'run-import',                         roles: ['admin'] },
diff --git a/app/lib/server/methods/getChannelHistory.js b/app/lib/server/methods/getChannelHistory.js
index c8e1208299ae5..4b630accb65ab 100644
--- a/app/lib/server/methods/getChannelHistory.js
+++ b/app/lib/server/methods/getChannelHistory.js
@@ -9,7 +9,7 @@ import { normalizeMessagesForUser } from '../../../utils/server/lib/normalizeMes
 import { Message } from '../../../../server/sdk';
 
 Meteor.methods({
-	getChannelHistory({ rid, latest, oldest, inclusive, offset = 0, count = 20, unreads }) {
+	getChannelHistory({ rid, latest, oldest, inclusive, offset = 0, count = 20, unreads, excludeTypes }) {
 		check(rid, String);
 
 		if (!Meteor.userId()) {
@@ -45,7 +45,7 @@ Meteor.methods({
 			queryOptions.fields = { editedAt: 0 };
 		}
 
-		const { records } = Promise.await(Message.get(fromUserId, { rid, latest, oldest, inclusive, queryOptions }));
+		const { records } = Promise.await(Message.get(fromUserId, { rid, latest, oldest, inclusive, excludeTypes, queryOptions }));
 
 		const messages = normalizeMessagesForUser(records, fromUserId);