diff --git a/models/activity/src/index.ts b/models/activity/src/index.ts
index a9db7be15a..8b7c096295 100644
--- a/models/activity/src/index.ts
+++ b/models/activity/src/index.ts
@@ -34,7 +34,8 @@ import {
   type IgnoreActivity,
   type Reaction,
   type SavedMessage,
-  type TxViewlet
+  type TxViewlet,
+  type ReplyProvider
 } from '@hcengineering/activity'
 import contact, { type Person } from '@hcengineering/contact'
 import core, {
@@ -264,6 +265,11 @@ export class TActivityMessagePreview extends TClass implements ActivityMessagePr
   presenter!: AnyComponent
 }
 
+@Model(activity.class.ReplyProvider, core.class.Doc, DOMAIN_MODEL)
+export class TReplyProvider extends TDoc implements ReplyProvider {
+  function!: Resource<(message: ActivityMessage) => Promise<void>>
+}
+
 export function createModel (builder: Builder): void {
   builder.createModel(
     TTxViewlet,
@@ -281,7 +287,8 @@ export function createModel (builder: Builder): void {
     TSavedMessage,
     TIgnoreActivity,
     TActivityReference,
-    TActivityMessagePreview
+    TActivityMessagePreview,
+    TReplyProvider
   )
 
   builder.mixin(activity.class.DocUpdateMessage, core.class.Class, view.mixin.ObjectPresenter, {
diff --git a/models/chunter/src/index.ts b/models/chunter/src/index.ts
index 1e03d46582..d61aaf1032 100644
--- a/models/chunter/src/index.ts
+++ b/models/chunter/src/index.ts
@@ -733,6 +733,10 @@ export function createModel (builder: Builder, options = { addApplication: true
     domain: DOMAIN_CHUNTER,
     disabled: [{ _class: 1 }, { space: 1 }, { modifiedBy: 1 }, { createdBy: 1 }, { createdOn: -1 }]
   })
+
+  builder.createDoc(activity.class.ReplyProvider, core.space.Model, {
+    function: chunter.function.ReplyToThread
+  })
 }
 
 export default chunter
diff --git a/models/chunter/src/plugin.ts b/models/chunter/src/plugin.ts
index a3744fd9c5..0b5550b1d2 100644
--- a/models/chunter/src/plugin.ts
+++ b/models/chunter/src/plugin.ts
@@ -99,7 +99,8 @@ export default mergeIds(chunterId, chunter, {
     CanDeleteMessage: '' as Resource<(doc?: Doc | Doc[]) => Promise<boolean>>,
     CanCopyMessageLink: '' as Resource<(doc?: Doc | Doc[]) => Promise<boolean>>,
     GetChunterSpaceLinkFragment: '' as Resource<(doc: Doc, props: Record<string, any>) => Promise<Location>>,
-    GetThreadLink: '' as Resource<(doc: Doc, props: Record<string, any>) => Promise<Location>>
+    GetThreadLink: '' as Resource<(doc: Doc, props: Record<string, any>) => Promise<Location>>,
+    ReplyToThread: '' as Resource<(doc: ActivityMessage) => Promise<void>>
   },
   filter: {
     ChatMessagesFilter: '' as Resource<(message: ActivityMessage, _class?: Ref<Doc>) => boolean>
diff --git a/plugins/chunter-resources/src/components/Replies.svelte b/plugins/activity-resources/src/components/Replies.svelte
similarity index 91%
rename from plugins/chunter-resources/src/components/Replies.svelte
rename to plugins/activity-resources/src/components/Replies.svelte
index 4e8057d280..5598bd6ebb 100644
--- a/plugins/chunter-resources/src/components/Replies.svelte
+++ b/plugins/activity-resources/src/components/Replies.svelte
@@ -13,10 +13,11 @@
 // limitations under the License.
 -->
 <script lang="ts">
-  import activity, { ActivityMessage } from '@hcengineering/activity'
   import { Person } from '@hcengineering/contact'
-  import { Avatar, personByIdStore } from '@hcengineering/contact-resources'
+  import { personByIdStore, Avatar } from '@hcengineering/contact-resources'
   import { Doc, IdMap, Ref, WithLookup } from '@hcengineering/core'
+  import { Label, TimeSince } from '@hcengineering/ui'
+  import activity, { ActivityMessage } from '@hcengineering/activity'
   import notification, {
     ActivityInboxNotification,
     DocNotifyContext,
@@ -24,14 +25,13 @@
     InboxNotificationsClient
   } from '@hcengineering/notification'
   import { getResource } from '@hcengineering/platform'
-  import { Label, TimeSince, getLocation, navigate } from '@hcengineering/ui'
-
-  import { buildThreadLink } from '../navigation'
+  import { getClient } from '@hcengineering/presentation'
 
   export let object: ActivityMessage
   export let embedded = false
   export let onReply: (() => void) | undefined = undefined
 
+  const client = getClient()
   const maxDisplayPersons = 5
 
   $: lastReply = object.lastReply ?? new Date().getTime()
@@ -77,7 +77,9 @@
       .slice(0, maxDisplayPersons - 1)
   }
 
-  function handleReply (e: MouseEvent): void {
+  const replyProvider = client.getModel().findAllSync(activity.class.ReplyProvider, {})[0]
+
+  async function handleReply (e: MouseEvent) {
     e.stopPropagation()
     e.preventDefault()
 
@@ -86,7 +88,10 @@
       return
     }
 
-    navigate(buildThreadLink(getLocation(), object.attachedTo, object.attachedToClass, object._id))
+    if (replyProvider) {
+      const fn = await getResource(replyProvider.function)
+      fn(object)
+    }
   }
 </script>
 
diff --git a/plugins/activity-resources/src/components/activity-message/ActivityMessageTemplate.svelte b/plugins/activity-resources/src/components/activity-message/ActivityMessageTemplate.svelte
index bc8ade35f1..3f46d11ae4 100644
--- a/plugins/activity-resources/src/components/activity-message/ActivityMessageTemplate.svelte
+++ b/plugins/activity-resources/src/components/activity-message/ActivityMessageTemplate.svelte
@@ -26,13 +26,13 @@
   import { getActions, restrictionStore } from '@hcengineering/view-resources'
 
   import ReactionsPresenter from '../reactions/ReactionsPresenter.svelte'
-  import ActivityMessageExtensionComponent from './ActivityMessageExtension.svelte'
   import ActivityMessagePresenter from './ActivityMessagePresenter.svelte'
   import ActivityMessageActions from '../ActivityMessageActions.svelte'
   import { isReactionMessage } from '../../activityMessagesUtils'
   import Bookmark from '../icons/Bookmark.svelte'
   import { savedMessagesStore } from '../../activity'
   import MessageTimestamp from '../MessageTimestamp.svelte'
+  import Replies from '../Replies.svelte'
 
   export let message: DisplayActivityMessage
   export let parentMessage: DisplayActivityMessage | undefined = undefined
@@ -85,11 +85,7 @@
     setTimeout(scrollToMessage, 100)
   }
 
-  void client
-    .findAll(activity.class.ActivityMessageExtension, { ofMessage: message._class })
-    .then((res: ActivityMessageExtension[]) => {
-      extensions = res
-    })
+  $: extensions = client.getModel().findAllSync(activity.class.ActivityMessageExtension, { ofMessage: message._class })
 
   function handleActionsOpened (): void {
     isActionsOpened = true
@@ -175,11 +171,7 @@
         <slot name="content" />
 
         {#if !hideFooter}
-          <ActivityMessageExtensionComponent
-            kind="footer"
-            {extensions}
-            props={{ object: message, embedded, onReply }}
-          />
+          <Replies {embedded} object={message} {onReply} />
         {/if}
         <ReactionsPresenter object={message} {readonly} />
         {#if parentMessage && showEmbedded}
diff --git a/plugins/activity/src/index.ts b/plugins/activity/src/index.ts
index d7b1b6184c..94c3302f7e 100644
--- a/plugins/activity/src/index.ts
+++ b/plugins/activity/src/index.ts
@@ -308,6 +308,10 @@ export interface SavedMessage extends Preference {
   attachedTo: Ref<ActivityMessage>
 }
 
+export interface ReplyProvider extends Doc {
+  function: Resource<(message: ActivityMessage) => Promise<void>>
+}
+
 /**
  * @public
  */
@@ -334,7 +338,8 @@ export default plugin(activityId, {
     ActivityExtension: '' as Ref<Class<ActivityExtension>>,
     Reaction: '' as Ref<Class<Reaction>>,
     SavedMessage: '' as Ref<Class<SavedMessage>>,
-    ActivityReference: '' as Ref<Class<ActivityReference>>
+    ActivityReference: '' as Ref<Class<ActivityReference>>,
+    ReplyProvider: '' as Ref<Class<ReplyProvider>>
   },
   icon: {
     Activity: '' as Asset,
diff --git a/plugins/chunter-resources/src/components/ChannelScrollView.svelte b/plugins/chunter-resources/src/components/ChannelScrollView.svelte
index d02ac3be88..ef7fa0d181 100644
--- a/plugins/chunter-resources/src/components/ChannelScrollView.svelte
+++ b/plugins/chunter-resources/src/components/ChannelScrollView.svelte
@@ -29,6 +29,7 @@
   import { InboxNotificationsClientImpl } from '@hcengineering/notification-resources'
   import { get } from 'svelte/store'
   import { tick, beforeUpdate, afterUpdate } from 'svelte'
+  import { getResource } from '@hcengineering/platform'
 
   import ActivityMessagesSeparator from './ChannelMessagesSeparator.svelte'
   import { filterChatMessages, getClosestDate, readChannelMessages } from '../utils'
@@ -58,7 +59,12 @@
   const client = getClient()
   const inboxClient = InboxNotificationsClientImpl.getClient()
   const contextByDocStore = inboxClient.contextByDoc
-  const filters = client.getModel().findAllSync(activity.class.ActivityMessagesFilter, {})
+
+  let filters: ActivityMessagesFilter[] = []
+  const filterResources = new Map<
+  Ref<ActivityMessagesFilter>,
+  (message: ActivityMessage, _class?: Ref<Doc>) => boolean
+  >()
 
   const messagesStore = provider.messagesStore
   const isLoadingStore = provider.isLoadingStore
@@ -93,15 +99,23 @@
 
   $: notifyContext = $contextByDocStore.get(objectId)
 
-  $: void filterChatMessages(messages, filters, objectClass, selectedFilters).then((filteredMessages) => {
-    displayMessages = filteredMessages
-  })
+  void client
+    .getModel()
+    .findAll(activity.class.ActivityMessagesFilter, {})
+    .then(async (res) => {
+      filters = res
+      for (const filter of filters) {
+        filterResources.set(filter._id, await getResource(filter.filter))
+      }
+    })
+
+  $: displayMessages = filterChatMessages(messages, filters, filterResources, objectClass, selectedFilters)
 
   inboxClient.inboxNotificationsByContext.subscribe(() => {
     readViewportMessages()
   })
 
-  function scrollToBottom (afterScrollFn?: () => void) {
+  function scrollToBottom (afterScrollFn?: () => void): void {
     if (scroller !== undefined && scrollElement !== undefined) {
       scroller.scrollBy(scrollElement.scrollHeight)
       updateSelectedDate()
@@ -109,9 +123,19 @@
     }
   }
 
-  function scrollToSeparator () {
-    if (separatorElement) {
+  function scrollToSeparator (): void {
+    if (separatorElement && scrollElement) {
+      const messagesElements = scrollContentBox?.getElementsByClassName('activityMessage')
+      const messagesHeight = displayMessages
+        .slice(separatorIndex)
+        .reduce((res, msg) => res + (messagesElements?.[msg._id as any]?.clientHeight ?? 0), 0)
+
       separatorElement.scrollIntoView()
+
+      if (messagesHeight >= scrollElement.clientHeight) {
+        scroller?.scrollBy(-50)
+      }
+
       updateShouldScrollToNew()
       readViewportMessages()
     }
@@ -373,7 +397,7 @@
     newTimestamp !== undefined
       ? displayMessages.findIndex((message) => (message.createdOn ?? 0) >= (newTimestamp ?? 0))
       : -1
-  $: void initializeScroll($isLoadingStore, separatorElement, separatorIndex)
+  $: void initializeScroll(isLoading, separatorElement, separatorIndex)
 
   let isInitialScrolling = true
   async function initializeScroll (isLoading: boolean, separatorElement?: HTMLDivElement, separatorIndex?: number) {
@@ -389,6 +413,7 @@
       scrollToMessage()
       isInitialScrolling = false
     } else if (separatorIndex === -1) {
+      await wait()
       isScrollInitialized = true
       shouldWaitAndRead = true
       autoscroll = true
diff --git a/plugins/chunter-resources/src/components/chat/specials/ChannelBrowser.svelte b/plugins/chunter-resources/src/components/chat/specials/ChannelBrowser.svelte
index 543d337bbb..e64a082cc9 100644
--- a/plugins/chunter-resources/src/components/chat/specials/ChannelBrowser.svelte
+++ b/plugins/chunter-resources/src/components/chat/specials/ChannelBrowser.svelte
@@ -24,13 +24,14 @@
     Space
   } from '@hcengineering/core'
   import { IntlString } from '@hcengineering/platform'
-  import presentation, { createQuery } from '@hcengineering/presentation'
+  import presentation, { createQuery, getClient } from '@hcengineering/presentation'
   import { AnyComponent, Button, Icon, Label, Scroller, SearchEdit, showPopup } from '@hcengineering/ui'
   import { FilterBar, FilterButton, SpacePresenter } from '@hcengineering/view-resources'
   import workbench from '@hcengineering/workbench'
   import { Channel } from '@hcengineering/chunter'
-  import { openChannel } from '../../../navigation'
+  import { InboxNotificationsClientImpl } from '@hcengineering/notification-resources'
 
+  import { openChannel } from '../../../navigation'
   import { getObjectIcon, joinChannel, leaveChannel } from '../../../utils'
   import chunter from './../../../plugin'
 
@@ -45,6 +46,9 @@
   const me = getCurrentAccount()._id
   const channelsQuery = createQuery()
 
+  const client = getClient()
+  const notificationsClient = InboxNotificationsClientImpl.getClient()
+
   const sort: SortingQuery<Space> = {
     name: SortingOrder.Ascending
   }
diff --git a/plugins/chunter-resources/src/index.ts b/plugins/chunter-resources/src/index.ts
index e57553dfb3..4d8236ddf2 100644
--- a/plugins/chunter-resources/src/index.ts
+++ b/plugins/chunter-resources/src/index.ts
@@ -48,7 +48,6 @@ import ChannelIcon from './components/ChannelIcon.svelte'
 import ThreadNotificationPresenter from './components/notification/ThreadNotificationPresenter.svelte'
 import ChatMessageNotificationLabel from './components/notification/ChatMessageNotificationLabel.svelte'
 import ChatAside from './components/chat/ChatAside.svelte'
-import Replies from './components/Replies.svelte'
 import ReplyToThreadAction from './components/ReplyToThreadAction.svelte'
 import ThreadMessagePreview from './components/threads/ThreadMessagePreview.svelte'
 import ChatMessagePreview from './components/chat-message/ChatMessagePreview.svelte'
@@ -65,7 +64,7 @@ import {
   leaveChannelAction,
   removeChannelAction
 } from './utils'
-import { chunterSpaceLinkFragmentProvider, getThreadLink, getMessageLink } from './navigation'
+import { chunterSpaceLinkFragmentProvider, getThreadLink, getMessageLink, replyToThread } from './navigation'
 
 export { default as ChatMessagesPresenter } from './components/chat-message/ChatMessagesPresenter.svelte'
 export { default as ChatMessagePopup } from './components/chat-message/ChatMessagePopup.svelte'
@@ -175,7 +174,6 @@ export default async (): Promise<Resources> => ({
     ChatMessageNotificationLabel,
     ThreadNotificationPresenter,
     ChatAside,
-    Replies,
     ReplyToThreadAction,
     ThreadMessagePreview,
     ChatMessagePreview
@@ -192,7 +190,8 @@ export default async (): Promise<Resources> => ({
     CanCopyMessageLink: canCopyMessageLink,
     GetChunterSpaceLinkFragment: chunterSpaceLinkFragmentProvider,
     GetUnreadThreadsCount: getUnreadThreadsCount,
-    GetThreadLink: getThreadLink
+    GetThreadLink: getThreadLink,
+    ReplyToThread: replyToThread
   },
   actionImpl: {
     ArchiveChannel,
diff --git a/plugins/chunter-resources/src/utils.ts b/plugins/chunter-resources/src/utils.ts
index 9e0b5cd4ed..0af57f74cc 100644
--- a/plugins/chunter-resources/src/utils.ts
+++ b/plugins/chunter-resources/src/utils.ts
@@ -29,7 +29,7 @@ import {
 } from '@hcengineering/core'
 import { getClient } from '@hcengineering/presentation'
 import { type AnySvelteComponent } from '@hcengineering/ui'
-import { type Asset, getResource, translate } from '@hcengineering/platform'
+import { type Asset, translate } from '@hcengineering/platform'
 import { classIcon, getDocLinkTitle, getDocTitle } from '@hcengineering/view-resources'
 import activity, {
   type ActivityMessage,
@@ -273,12 +273,13 @@ export function getClosestDate (selectedDate: Timestamp, dates: Timestamp[]): Ti
   return closestDate
 }
 
-export async function filterChatMessages (
+export function filterChatMessages (
   messages: DisplayActivityMessage[],
   filters: ActivityMessagesFilter[],
+  filterResources: Map<Ref<ActivityMessagesFilter>, (message: ActivityMessage, _class?: Ref<Doc>) => boolean>,
   objectClass: Ref<Class<Doc>>,
   selectedIds: Array<Ref<ActivityMessagesFilter>>
-): Promise<DisplayActivityMessage[]> {
+): DisplayActivityMessage[] {
   if (selectedIds.length === 0 || selectedIds.includes(activity.ids.AllFilter)) {
     return messages
   }
@@ -291,8 +292,10 @@ export async function filterChatMessages (
   const filtersFns: Array<(message: ActivityMessage, _class?: Ref<Doc>) => boolean> = []
 
   for (const filter of selectedFilters) {
-    const filterFn = await getResource(filter.filter)
-    filtersFns.push(filterFn)
+    const filterFn = filterResources.get(filter._id)
+    if (filterFn !== undefined) {
+      filtersFns.push(filterFn)
+    }
   }
 
   return messages.filter((message) => filtersFns.some((filterFn) => filterFn(message, objectClass)))
diff --git a/server-plugins/chunter-resources/src/index.ts b/server-plugins/chunter-resources/src/index.ts
index 3f9eed5674..5a99058d97 100644
--- a/server-plugins/chunter-resources/src/index.ts
+++ b/server-plugins/chunter-resources/src/index.ts
@@ -432,6 +432,16 @@ async function OnChannelMembersChanged (tx: TxUpdateDoc<Channel>, control: Trigg
     )
   }
 
+  if (added.length > 0) {
+    res.push(
+      control.txFactory.createTxMixin(tx.objectId, tx.objectClass, tx.objectSpace, notification.mixin.Collaborators, {
+        $push: {
+          collaborators: { $each: added, $position: 0 }
+        }
+      })
+    )
+  }
+
   for (const addedMember of added) {
     const context = allContexts.find(({ user }) => user === addedMember)
 
@@ -457,16 +467,8 @@ async function OnChannelMembersChanged (tx: TxUpdateDoc<Channel>, control: Trigg
 
   const contextsToRemove = allContexts.filter(({ user }) => removed.includes(user))
 
-  if (contextsToRemove.length === 0) {
-    return res
-  }
-
-  const channel = (await control.findAll(chunter.class.Channel, { _id: tx.objectId }))[0]
-
-  if (channel !== undefined) {
-    for (const context of contextsToRemove) {
-      res.push(control.txFactory.createTxRemoveDoc(context._class, context.space, context._id))
-    }
+  for (const context of contextsToRemove) {
+    res.push(control.txFactory.createTxRemoveDoc(context._class, context.space, context._id))
   }
 
   return res