diff --git a/plugins/chunter-resources/src/components/ChannelScrollView.svelte b/plugins/chunter-resources/src/components/ChannelScrollView.svelte
index 24af96e288..b8f88da1c1 100644
--- a/plugins/chunter-resources/src/components/ChannelScrollView.svelte
+++ b/plugins/chunter-resources/src/components/ChannelScrollView.svelte
@@ -13,36 +13,36 @@
 // limitations under the License.
 -->
 <script lang="ts">
-  import { Class, Doc, getDay, Ref, Timestamp } from '@hcengineering/core'
-  import { getClient } from '@hcengineering/presentation'
   import activity, {
     ActivityExtension,
     ActivityMessage,
     ActivityMessagesFilter,
     DisplayActivityMessage
   } from '@hcengineering/activity'
-  import { Loading, Scroller, ScrollParams } from '@hcengineering/ui'
   import {
     ActivityExtension as ActivityExtensionComponent,
     ActivityMessagePresenter,
     canGroupMessages
   } from '@hcengineering/activity-resources'
+  import { Class, Doc, getDay, Ref, Timestamp } from '@hcengineering/core'
   import { InboxNotificationsClientImpl } from '@hcengineering/notification-resources'
-  import { get } from 'svelte/store'
-  import { tick, beforeUpdate, afterUpdate, onMount, onDestroy } from 'svelte'
   import { getResource } from '@hcengineering/platform'
+  import { getClient } from '@hcengineering/presentation'
+  import { Loading, Scroller, ScrollParams } from '@hcengineering/ui'
+  import { afterUpdate, beforeUpdate, onDestroy, onMount, tick } from 'svelte'
+  import { get } from 'svelte/store'
 
-  import ActivityMessagesSeparator from './ChannelMessagesSeparator.svelte'
+  import { ChannelDataProvider, MessageMetadata } from '../channelDataProvider'
   import {
+    chatReadMessagesStore,
     filterChatMessages,
     getClosestDate,
     readChannelMessages,
-    chatReadMessagesStore,
     recheckNotifications
   } from '../utils'
-  import HistoryLoading from './LoadingHistory.svelte'
-  import { ChannelDataProvider, MessageMetadata } from '../channelDataProvider'
+  import ActivityMessagesSeparator from './ChannelMessagesSeparator.svelte'
   import JumpToDateSelector from './JumpToDateSelector.svelte'
+  import HistoryLoading from './LoadingHistory.svelte'
 
   export let provider: ChannelDataProvider
   export let object: Doc | undefined
@@ -313,6 +313,9 @@
     return messageRect.top >= containerRect.top && messageRect.bottom - messageRect.height / 2 <= containerRect.bottom
   }
 
+  const messagesToReadAccumulator: DisplayActivityMessage[] = []
+  let messagesToReadAccumulatorTimer: any
+
   function readViewportMessages (): void {
     if (!scrollElement || !scrollContentBox) {
       return
@@ -320,7 +323,6 @@
 
     const containerRect = scrollElement.getBoundingClientRect()
 
-    const messagesToRead: DisplayActivityMessage[] = []
     const messagesElements = scrollContentBox?.getElementsByClassName('activityMessage')
 
     for (const message of displayMessages) {
@@ -331,11 +333,15 @@
       }
 
       if (messageInView(msgElement, containerRect)) {
-        messagesToRead.push(message)
+        messagesToReadAccumulator.push(message)
       }
     }
 
-    void readChannelMessages(messagesToRead, notifyContext)
+    clearTimeout(messagesToReadAccumulatorTimer)
+    messagesToReadAccumulatorTimer = setTimeout(() => {
+      const messagesToRead = [...messagesToReadAccumulator]
+      void readChannelMessages(messagesToRead, notifyContext)
+    }, 500)
   }
 
   function updateSelectedDate (): void {
diff --git a/plugins/chunter-resources/src/utils.ts b/plugins/chunter-resources/src/utils.ts
index 9c39b9b2aa..b9b985095e 100644
--- a/plugins/chunter-resources/src/utils.ts
+++ b/plugins/chunter-resources/src/utils.ts
@@ -12,44 +12,45 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 //
+import activity, {
+  type ActivityMessage,
+  type ActivityMessagesFilter,
+  type DisplayActivityMessage,
+  type DisplayDocUpdateMessage,
+  type DocUpdateMessage
+} from '@hcengineering/activity'
 import { type Channel, type ChatMessage, type DirectMessage, type ThreadMessage } from '@hcengineering/chunter'
-import contact, { type Employee, getName, type Person, type PersonAccount } from '@hcengineering/contact'
-import { employeeByIdStore, PersonIcon } from '@hcengineering/contact-resources'
+import contact, { getName, type Employee, type Person, type PersonAccount } from '@hcengineering/contact'
+import { PersonIcon, employeeByIdStore } from '@hcengineering/contact-resources'
 import {
+  generateId,
+  getCurrentAccount,
   type Account,
   type Class,
   type Client,
   type Doc,
-  getCurrentAccount,
   type IdMap,
   type Ref,
   type Space,
   type Timestamp
 } from '@hcengineering/core'
-import { getClient } from '@hcengineering/presentation'
-import { type AnySvelteComponent } from '@hcengineering/ui'
-import { type Asset, translate } from '@hcengineering/platform'
-import { classIcon, getDocLinkTitle, getDocTitle } from '@hcengineering/view-resources'
-import activity, {
-  type ActivityMessage,
-  type ActivityMessagesFilter,
-  type DisplayActivityMessage,
-  type DisplayDocUpdateMessage,
-  type DocUpdateMessage
-} from '@hcengineering/activity'
+import notification, { type DocNotifyContext, type InboxNotification } from '@hcengineering/notification'
 import {
-  archiveContextNotifications,
   InboxNotificationsClientImpl,
+  archiveContextNotifications,
   isActivityNotification,
   isMentionNotification
 } from '@hcengineering/notification-resources'
-import notification, { type DocNotifyContext } from '@hcengineering/notification'
-import { get, type Unsubscriber, writable } from 'svelte/store'
+import { translate, type Asset } from '@hcengineering/platform'
+import { getClient } from '@hcengineering/presentation'
+import { type AnySvelteComponent } from '@hcengineering/ui'
+import { classIcon, getDocLinkTitle, getDocTitle } from '@hcengineering/view-resources'
+import { get, writable, type Unsubscriber } from 'svelte/store'
 
-import chunter from './plugin'
-import DirectIcon from './components/DirectIcon.svelte'
 import ChannelIcon from './components/ChannelIcon.svelte'
+import DirectIcon from './components/DirectIcon.svelte'
 import { resetChunterLocIfEqual } from './navigation'
+import chunter from './plugin'
 
 export async function getDmName (client: Client, space?: Space): Promise<string> {
   if (space === undefined) {
@@ -366,6 +367,9 @@ function getAllIds (messages: DisplayActivityMessage[]): Array<Ref<ActivityMessa
     .flat()
 }
 
+let toReadTimer: any
+const toRead = new Set<Ref<InboxNotification>>()
+
 export function recheckNotifications (context: DocNotifyContext): void {
   const client = getClient()
   const inboxClient = InboxNotificationsClientImpl.getClient()
@@ -378,7 +382,7 @@ export function recheckNotifications (context: DocNotifyContext): void {
 
   const notifications = get(inboxClient.inboxNotificationsByContext).get(context._id) ?? []
 
-  const toRead = notifications
+  notifications
     .filter((it) => {
       if (it.isViewed) {
         return false
@@ -394,9 +398,18 @@ export function recheckNotifications (context: DocNotifyContext): void {
 
       return false
     })
-    .map((n) => n._id)
-
-  void inboxClient.readNotifications(client, toRead)
+    .forEach((n) => toRead.add(n._id))
+
+  clearTimeout(toReadTimer)
+  toReadTimer = setTimeout(() => {
+    const toReadData = Array.from(toRead)
+    toRead.clear()
+    void (async () => {
+      const _client = client.apply(generateId())
+      await inboxClient.readNotifications(_client, toReadData)
+      await _client.commit()
+    })()
+  }, 500)
 }
 
 export async function readChannelMessages (
@@ -408,38 +421,42 @@ export async function readChannelMessages (
   }
 
   const inboxClient = InboxNotificationsClientImpl.getClient()
-  const client = getClient()
 
-  const readMessages = get(chatReadMessagesStore)
-  const allIds = getAllIds(messages).filter((id) => !readMessages.has(id))
+  const client = getClient().apply(generateId())
+  try {
+    const readMessages = get(chatReadMessagesStore)
+    const allIds = getAllIds(messages).filter((id) => !readMessages.has(id))
 
-  const notifications = get(inboxClient.activityInboxNotifications)
-    .filter(({ _id, attachedTo }) => allIds.includes(attachedTo))
-    .map((n) => n._id)
+    const notifications = get(inboxClient.activityInboxNotifications)
+      .filter(({ _id, attachedTo }) => allIds.includes(attachedTo))
+      .map((n) => n._id)
 
-  const relatedMentions = get(inboxClient.otherInboxNotifications)
-    .filter((n) => !n.isViewed && isMentionNotification(n) && allIds.includes(n.mentionedIn as Ref<ActivityMessage>))
-    .map((n) => n._id)
+    const relatedMentions = get(inboxClient.otherInboxNotifications)
+      .filter((n) => !n.isViewed && isMentionNotification(n) && allIds.includes(n.mentionedIn as Ref<ActivityMessage>))
+      .map((n) => n._id)
 
-  chatReadMessagesStore.update((store) => new Set([...store, ...allIds]))
+    chatReadMessagesStore.update((store) => new Set([...store, ...allIds]))
 
-  void inboxClient.readNotifications(client, [...notifications, ...relatedMentions])
+    await inboxClient.readNotifications(client, [...notifications, ...relatedMentions])
 
-  if (context === undefined) {
-    return
-  }
-
-  const storedTimestampUpdates = get(contextsTimestampStore).get(context._id)
-  const newTimestamp = messages[messages.length - 1].createdOn ?? 0
-  const prevTimestamp = Math.max(storedTimestampUpdates ?? 0, context.lastViewedTimestamp ?? 0)
+    if (context === undefined) {
+      return
+    }
 
-  if (prevTimestamp < newTimestamp) {
-    context.lastViewedTimestamp = newTimestamp
-    contextsTimestampStore.update((store) => {
-      store.set(context._id, newTimestamp)
-      return store
-    })
-    void client.update(context, { lastViewedTimestamp: newTimestamp })
+    const storedTimestampUpdates = get(contextsTimestampStore).get(context._id)
+    const newTimestamp = messages[messages.length - 1].createdOn ?? 0
+    const prevTimestamp = Math.max(storedTimestampUpdates ?? 0, context.lastViewedTimestamp ?? 0)
+
+    if (prevTimestamp < newTimestamp) {
+      context.lastViewedTimestamp = newTimestamp
+      contextsTimestampStore.update((store) => {
+        store.set(context._id, newTimestamp)
+        return store
+      })
+      await client.update(context, { lastViewedTimestamp: newTimestamp })
+    }
+  } finally {
+    await client.commit()
   }
 }
 
diff --git a/plugins/view-resources/src/components/viewer/ImageViewer.svelte b/plugins/view-resources/src/components/viewer/ImageViewer.svelte
index 2d8742d71f..f93b161d56 100644
--- a/plugins/view-resources/src/components/viewer/ImageViewer.svelte
+++ b/plugins/view-resources/src/components/viewer/ImageViewer.svelte
@@ -15,6 +15,7 @@
 <script lang="ts">
   import { type Blob, type Ref } from '@hcengineering/core'
   import { getBlobRef, type BlobMetadata } from '@hcengineering/presentation'
+  import { Loading } from '@hcengineering/ui'
 
   export let value: Blob | Ref<Blob>
   export let name: string
@@ -26,15 +27,25 @@
   $: height = metadata?.originalHeight
     ? `min(${metadata.originalHeight / metadata?.pixelRatio ?? 1}px, ${fit ? '100%' : '80vh'})`
     : '100%'
+  let loading = true
 </script>
 
 {#await p then blobRef}
+  {#if loading}
+    <div class="flex justify-center">
+      <Loading />
+    </div>
+  {/if}
   <img
+    on:load={(evt) => {
+      loading = false
+    }}
     class="object-contain mx-auto"
     style:max-width={width}
     style:max-height={height}
     src={blobRef.src}
     srcset={blobRef.srcset}
     alt={name}
+    style:height={loading ? '0' : ''}
   />
 {/await}
diff --git a/server/backup/src/backup.ts b/server/backup/src/backup.ts
index ea256d4e0d..2676fda96a 100644
--- a/server/backup/src/backup.ts
+++ b/server/backup/src/backup.ts
@@ -1198,6 +1198,10 @@ export async function restore (
     async function sendChunk (doc: Doc | undefined, len: number): Promise<void> {
       if (doc !== undefined) {
         docsToAdd.delete(doc._id)
+        if (opt.recheck === true) {
+          // We need to clear %hash% in case our is wrong.
+          delete (doc as any)['%hash%']
+        }
         docs.push(doc)
       }
       sendSize = sendSize + len
diff --git a/server/front/src/index.ts b/server/front/src/index.ts
index 570e0076c1..27fddd533c 100644
--- a/server/front/src/index.ts
+++ b/server/front/src/index.ts
@@ -15,7 +15,7 @@
 //
 
 import { Analytics } from '@hcengineering/analytics'
-import { MeasureContext, Blob as PlatformBlob, WorkspaceId, metricsAggregate } from '@hcengineering/core'
+import { MeasureContext, Blob as PlatformBlob, WorkspaceId, metricsAggregate, type Ref } from '@hcengineering/core'
 import { Token, decodeToken } from '@hcengineering/server-token'
 import { StorageAdapter, removeAllObjects } from '@hcengineering/storage'
 import bp from 'body-parser'
@@ -798,8 +798,22 @@ async function getGeneratePreview (
       pipeline.destroy()
 
       // Add support of avif as well.
-      await config.storageAdapter.put(ctx, payload.workspace, sizeId, dataBuff, contentType, dataBuff.length)
-      return (await config.storageAdapter.stat(ctx, payload.workspace, sizeId)) ?? blob
+      const upload = await config.storageAdapter.put(
+        ctx,
+        payload.workspace,
+        sizeId,
+        dataBuff,
+        contentType,
+        dataBuff.length
+      )
+      return {
+        ...blob,
+        _id: sizeId as Ref<PlatformBlob>,
+        size: dataBuff.length,
+        contentType,
+        etag: upload.etag,
+        storageId: sizeId
+      }
     } catch (err: any) {
       Analytics.handleError(err)
       ctx.error('failed to resize image', {