diff --git a/changelog.d/5692.misc b/changelog.d/5692.misc
new file mode 100644
index 0000000000..66f1d35eb0
--- /dev/null
+++ b/changelog.d/5692.misc
@@ -0,0 +1 @@
+Implement threads beta opt-in mechanism to notify users about threads
\ No newline at end of file
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/timeline/SendingEventsDataSource.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/timeline/SendingEventsDataSource.kt
index cb61222de7..637267a9b1 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/timeline/SendingEventsDataSource.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/timeline/SendingEventsDataSource.kt
@@ -45,9 +45,11 @@ internal class RealmSendingEventsDataSource(
     private var frozenSendingTimelineEvents: RealmList<TimelineEventEntity>? = null
 
     private val sendingTimelineEventsListener = RealmChangeListener<RealmList<TimelineEventEntity>> { events ->
-        uiEchoManager.onSentEventsInDatabase(events.map { it.eventId })
-        updateFrozenResults(events)
-        onEventsUpdated(false)
+        if (events.isValid) {
+            uiEchoManager.onSentEventsInDatabase(events.map { it.eventId })
+            updateFrozenResults(events)
+            onEventsUpdated(false)
+        }
     }
 
     override fun start() {
diff --git a/vector-config/src/main/res/values/urls.xml b/vector-config/src/main/res/values/urls.xml
new file mode 100644
index 0000000000..22e3a9ac72
--- /dev/null
+++ b/vector-config/src/main/res/values/urls.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <!-- This file contains url values-->
+
+    <string name="threads_learn_more_url" translatable="false">https://element.io/help#threads</string>
+</resources>
\ No newline at end of file
diff --git a/vector/src/main/java/im/vector/app/core/epoxy/bottomsheet/BottomSheetActionItem.kt b/vector/src/main/java/im/vector/app/core/epoxy/bottomsheet/BottomSheetActionItem.kt
index 854a5d3419..ed3d55fca9 100644
--- a/vector/src/main/java/im/vector/app/core/epoxy/bottomsheet/BottomSheetActionItem.kt
+++ b/vector/src/main/java/im/vector/app/core/epoxy/bottomsheet/BottomSheetActionItem.kt
@@ -71,6 +71,9 @@ abstract class BottomSheetActionItem : VectorEpoxyModel<BottomSheetActionItem.Ho
     @EpoxyAttribute
     var destructive = false
 
+    @EpoxyAttribute
+    var showBetaLabel = false
+
     @EpoxyAttribute(EpoxyAttribute.Option.DoNotHash)
     lateinit var listener: ClickListener
 
@@ -106,6 +109,7 @@ abstract class BottomSheetActionItem : VectorEpoxyModel<BottomSheetActionItem.Ho
         } else {
             holder.text.setCompoundDrawablesWithIntrinsicBounds(null, null, null, null)
         }
+        holder.betaLabel.isVisible = showBetaLabel
     }
 
     class Holder : VectorEpoxyHolder() {
@@ -113,5 +117,6 @@ abstract class BottomSheetActionItem : VectorEpoxyModel<BottomSheetActionItem.Ho
         val icon by bind<ImageView>(R.id.actionIcon)
         val text by bind<TextView>(R.id.actionTitle)
         val selected by bind<ImageView>(R.id.actionSelected)
+        val betaLabel by bind<TextView>(R.id.actionBetaTextView)
     }
 }
diff --git a/vector/src/main/java/im/vector/app/features/home/room/detail/TimelineFragment.kt b/vector/src/main/java/im/vector/app/features/home/room/detail/TimelineFragment.kt
index ffb6ab6d26..a903b87669 100644
--- a/vector/src/main/java/im/vector/app/features/home/room/detail/TimelineFragment.kt
+++ b/vector/src/main/java/im/vector/app/features/home/room/detail/TimelineFragment.kt
@@ -25,6 +25,7 @@ import android.os.Build
 import android.os.Bundle
 import android.text.Spannable
 import android.text.format.DateUtils
+import android.text.method.LinkMovementMethod
 import android.view.HapticFeedbackConstants
 import android.view.KeyEvent
 import android.view.LayoutInflater
@@ -170,6 +171,7 @@ import im.vector.app.features.home.room.detail.timeline.url.PreviewUrlRetriever
 import im.vector.app.features.home.room.detail.upgrade.MigrateRoomBottomSheet
 import im.vector.app.features.home.room.detail.views.RoomDetailLazyLoadedViews
 import im.vector.app.features.home.room.detail.widget.RoomWidgetsBottomSheet
+import im.vector.app.features.home.room.threads.ThreadsManager
 import im.vector.app.features.home.room.threads.arguments.ThreadTimelineArgs
 import im.vector.app.features.html.EventHtmlRenderer
 import im.vector.app.features.html.PillImageSpan
@@ -252,6 +254,7 @@ class TimelineFragment @Inject constructor(
         private val notificationDrawerManager: NotificationDrawerManager,
         private val eventHtmlRenderer: EventHtmlRenderer,
         private val vectorPreferences: VectorPreferences,
+        private val threadsManager: ThreadsManager,
         private val colorProvider: ColorProvider,
         private val dimensionConverter: DimensionConverter,
         private val userPreferencesProvider: UserPreferencesProvider,
@@ -2213,7 +2216,7 @@ class TimelineFragment @Inject constructor(
             }
             is EventSharedAction.ReplyInThread              -> {
                 if (withState(messageComposerViewModel) { it.isVoiceMessageIdle }) {
-                    navigateToThreadTimeline(action.eventId, action.startsThread)
+                    onReplyInThreadClicked(action)
                 } else {
                     requireActivity().toast(R.string.error_voice_message_cannot_reply_or_edit)
                 }
@@ -2369,6 +2372,14 @@ class TimelineFragment @Inject constructor(
                 .show()
     }
 
+    private fun onReplyInThreadClicked(action: EventSharedAction.ReplyInThread) {
+        if (vectorPreferences.areThreadMessagesEnabled()) {
+            navigateToThreadTimeline(action.eventId, action.startsThread)
+        } else {
+            displayThreadsBetaOptInDialog()
+        }
+    }
+
     /**
      * Navigate to Threads timeline for the specified rootThreadEventId
      * using the ThreadsActivity
@@ -2388,6 +2399,25 @@ class TimelineFragment @Inject constructor(
         }
     }
 
+    private fun displayThreadsBetaOptInDialog() {
+            activity?.let {
+                MaterialAlertDialogBuilder(it)
+                        .setTitle(R.string.threads_beta_enable_notice_title)
+                        .setMessage(threadsManager.getBetaEnableThreadsMessage())
+                        .setCancelable(true)
+                        .setNegativeButton(R.string.action_not_now) { _, _ -> }
+                        .setPositiveButton(R.string.action_try_it_out) { _, _ ->
+                            threadsManager.enableThreadsAndRestart(it)
+                        }
+                        .show()
+                        ?.findViewById<TextView>(android.R.id.message)
+                        ?.apply {
+                            linksClickable = true
+                            movementMethod = LinkMovementMethod.getInstance()
+                        }
+            }
+        }
+
     /**
      * Navigate to Threads list for the current room
      * using the ThreadsActivity
diff --git a/vector/src/main/java/im/vector/app/features/home/room/detail/timeline/action/MessageActionsEpoxyController.kt b/vector/src/main/java/im/vector/app/features/home/room/detail/timeline/action/MessageActionsEpoxyController.kt
index 27937047a5..307be220d3 100644
--- a/vector/src/main/java/im/vector/app/features/home/room/detail/timeline/action/MessageActionsEpoxyController.kt
+++ b/vector/src/main/java/im/vector/app/features/home/room/detail/timeline/action/MessageActionsEpoxyController.kt
@@ -43,6 +43,7 @@ import im.vector.app.features.location.INITIAL_MAP_ZOOM_IN_TIMELINE
 import im.vector.app.features.location.UrlMapProvider
 import im.vector.app.features.location.toLocationData
 import im.vector.app.features.media.ImageContentRenderer
+import im.vector.app.features.settings.VectorPreferences
 import im.vector.lib.core.utils.epoxy.charsequence.toEpoxyCharSequence
 import org.matrix.android.sdk.api.extensions.orFalse
 import org.matrix.android.sdk.api.extensions.orTrue
@@ -64,6 +65,7 @@ class MessageActionsEpoxyController @Inject constructor(
         private val errorFormatter: ErrorFormatter,
         private val spanUtils: SpanUtils,
         private val eventDetailsFormatter: EventDetailsFormatter,
+        private val vectorPreferences: VectorPreferences,
         private val dateFormatter: VectorDateFormatter,
         private val urlMapProvider: UrlMapProvider,
         private val locationPinProvider: LocationPinProvider
@@ -187,6 +189,8 @@ class MessageActionsEpoxyController @Inject constructor(
                     id("separator_$index")
                 }
             } else {
+                val showBetaLabel = action.shouldShowBetaLabel()
+
                 bottomSheetActionItem {
                     id("action_$index")
                     iconRes(action.iconResId)
@@ -195,6 +199,7 @@ class MessageActionsEpoxyController @Inject constructor(
                     expanded(state.expendedReportContentMenu)
                     listener { host.listener?.didSelectMenuAction(action) }
                     destructive(action.destructive)
+                    showBetaLabel(showBetaLabel)
                 }
 
                 if (action is EventSharedAction.ReportContent && state.expendedReportContentMenu) {
@@ -217,6 +222,9 @@ class MessageActionsEpoxyController @Inject constructor(
         }
     }
 
+    private fun EventSharedAction.shouldShowBetaLabel(): Boolean =
+            this is EventSharedAction.ReplyInThread && !vectorPreferences.areThreadMessagesEnabled()
+
     interface MessageActionsEpoxyControllerListener : TimelineEventController.UrlClickCallback {
         fun didSelectMenuAction(eventAction: EventSharedAction)
     }
diff --git a/vector/src/main/java/im/vector/app/features/home/room/detail/timeline/action/MessageActionsViewModel.kt b/vector/src/main/java/im/vector/app/features/home/room/detail/timeline/action/MessageActionsViewModel.kt
index aaaecb0a13..9a73afd897 100644
--- a/vector/src/main/java/im/vector/app/features/home/room/detail/timeline/action/MessageActionsViewModel.kt
+++ b/vector/src/main/java/im/vector/app/features/home/room/detail/timeline/action/MessageActionsViewModel.kt
@@ -450,7 +450,8 @@ class MessageActionsViewModel @AssistedInject constructor(
     private fun canReplyInThread(event: TimelineEvent,
                                  messageContent: MessageContent?,
                                  actionPermissions: ActionPermissions): Boolean {
-        if (!vectorPreferences.areThreadMessagesEnabled()) return false
+        // We let reply in thread visible even if threads are not enabled, with an enhanced flow to attract users
+//        if (!vectorPreferences.areThreadMessagesEnabled()) return false
         if (initialState.isFromThreadTimeline) return false
         if (event.root.isThread()) return false
         if (event.root.getClearType() != EventType.MESSAGE &&
diff --git a/vector/src/main/java/im/vector/app/features/home/room/threads/ThreadsManager.kt b/vector/src/main/java/im/vector/app/features/home/room/threads/ThreadsManager.kt
new file mode 100644
index 0000000000..469a12019a
--- /dev/null
+++ b/vector/src/main/java/im/vector/app/features/home/room/threads/ThreadsManager.kt
@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2022 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.features.home.room.threads
+
+import android.app.Activity
+import android.text.Spanned
+import androidx.core.text.HtmlCompat
+import im.vector.app.R
+import im.vector.app.core.resources.StringProvider
+import im.vector.app.features.MainActivity
+import im.vector.app.features.MainActivityArgs
+import im.vector.app.features.settings.VectorPreferences
+import org.matrix.android.sdk.internal.database.lightweight.LightweightSettingsStorage
+import javax.inject.Inject
+
+/**
+ * The class is responsible for handling thread specific tasks
+ */
+class ThreadsManager @Inject constructor(
+        private val vectorPreferences: VectorPreferences,
+        private val lightweightSettingsStorage: LightweightSettingsStorage,
+        private val stringProvider: StringProvider
+) {
+
+    /**
+     * Enable threads and invoke an initial sync. The initial sync is mandatory in order to change
+     * the already saved DB schema for already received messages
+     */
+    fun enableThreadsAndRestart(activity: Activity) {
+        vectorPreferences.setThreadMessagesEnabled()
+        lightweightSettingsStorage.setThreadMessagesEnabled(vectorPreferences.areThreadMessagesEnabled())
+        MainActivity.restartApp(activity, MainActivityArgs(clearCache = true))
+    }
+
+    /**
+     * Generates and return an Html spanned string to be rendered especially in dialogs
+     */
+    fun getBetaEnableThreadsMessage(): Spanned {
+        val learnMore = stringProvider.getString(R.string.action_learn_more)
+        val learnMoreUrl = stringProvider.getString(R.string.threads_learn_more_url)
+        val href = "<a href='$learnMoreUrl'>$learnMore</a>.<br><br>"
+        val message = stringProvider.getString(R.string.threads_beta_enable_notice_message, href)
+        return HtmlCompat.fromHtml(message, HtmlCompat.FROM_HTML_MODE_LEGACY)
+    }
+}
diff --git a/vector/src/main/java/im/vector/app/features/settings/VectorSettingsLabsFragment.kt b/vector/src/main/java/im/vector/app/features/settings/VectorSettingsLabsFragment.kt
index fb2fb2b490..50ef864dbf 100644
--- a/vector/src/main/java/im/vector/app/features/settings/VectorSettingsLabsFragment.kt
+++ b/vector/src/main/java/im/vector/app/features/settings/VectorSettingsLabsFragment.kt
@@ -29,7 +29,6 @@ import javax.inject.Inject
 class VectorSettingsLabsFragment @Inject constructor(
         private val vectorPreferences: VectorPreferences,
         private val lightweightSettingsStorage: LightweightSettingsStorage
-
 ) : VectorSettingsBaseFragment() {
 
     override var titleRes = R.string.room_settings_labs_pref_title
diff --git a/vector/src/main/res/layout/item_bottom_sheet_action.xml b/vector/src/main/res/layout/item_bottom_sheet_action.xml
index bffcb79df6..e5230620d4 100644
--- a/vector/src/main/res/layout/item_bottom_sheet_action.xml
+++ b/vector/src/main/res/layout/item_bottom_sheet_action.xml
@@ -82,4 +82,27 @@
         tools:ignore="MissingPrefix"
         tools:visibility="visible" />
 
+
+    <TextView
+        android:id="@+id/actionBetaTextView"
+        style="@style/Widget.Vector.TextView.Caption"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center"
+        android:background="@drawable/notification_badge"
+        android:backgroundTint="@color/palette_azure"
+        android:gravity="center"
+        android:paddingStart="10dp"
+        android:paddingTop="3dp"
+        android:paddingEnd="10dp"
+        android:layout_marginEnd="1dp"
+        android:paddingBottom="3dp"
+        android:visibility="gone"
+        tools:visibility="visible"
+        android:text="@string/beta_title_bottom_sheet_action"
+        android:textColor="@color/palette_white"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toStartOf="@id/actionSelected"
+        app:layout_constraintTop_toTopOf="parent"/>
+
 </androidx.constraintlayout.widget.ConstraintLayout>
diff --git a/vector/src/main/res/values/strings.xml b/vector/src/main/res/values/strings.xml
index e61d3f9753..0ab450421c 100644
--- a/vector/src/main/res/values/strings.xml
+++ b/vector/src/main/res/values/strings.xml
@@ -360,6 +360,7 @@
     <string name="action_enable">Enable</string>
     <string name="action_disable">Disable</string>
     <string name="action_not_now">Not now</string>
+    <string name="action_try_it_out">Try it out</string>
     <string name="action_agree">Agree</string>
     <string name="action_change">"Change"</string>
     <string name="action_remove">Remove</string>
@@ -384,6 +385,7 @@
     <string name="action_play">Play</string>
     <string name="action_dismiss">Dismiss</string>
     <string name="action_reset">Reset</string>
+    <string name="action_learn_more">Learn more</string>
 
     <string name="copied_to_clipboard">Copied to clipboard</string>
 
@@ -734,6 +736,9 @@
     <string name="search_thread_from_a_thread">From a Thread</string>
     <string name="threads_notice_migration_title">Threads Approaching Beta 🎉</string>
     <string name="threads_notice_migration_message">We’re getting closer to releasing a public Beta for Threads.\n\nAs we prepare for it, we need to make some changes: threads created before this point will be displayed as regular replies.\n\nThis will be a one-off transition as Threads are now part of the Matrix specification.</string>
+    <string name="threads_beta_enable_notice_title">Threads Beta</string>
+    <!-- %s will be replaced with action_learn_more string resource that will be clickable(url redirection)  -->
+    <string name="threads_beta_enable_notice_message">Threads help keep your conversations on-topic and easy to track. %sEnabling threads will refresh the app. This may take longer for some accounts.</string>
 
     <!-- Search -->
     <string name="search_hint">Search</string>
@@ -1643,6 +1648,7 @@
     <string name="send_suggestion_sent">Thanks, the suggestion has been successfully sent</string>
     <string name="send_suggestion_failed">The suggestion failed to be sent (%s)</string>
 
+    <string name="beta_title_bottom_sheet_action">BETA</string>
     <string name="send_feedback_space_title">Spaces feedback</string>
     <string name="feedback">Feedback</string>
     <string name="send_feedback_space_info">You’re using a beta version of spaces. Your feedback will help inform the next versions. Your platform and username will be noted to help us use your feedback as much as we can.</string>