diff --git a/appconfig/src/main/kotlin/io/element/android/appconfig/LearnMoreConfig.kt b/appconfig/src/main/kotlin/io/element/android/appconfig/LearnMoreConfig.kt
index c0c152142e..855586892a 100644
--- a/appconfig/src/main/kotlin/io/element/android/appconfig/LearnMoreConfig.kt
+++ b/appconfig/src/main/kotlin/io/element/android/appconfig/LearnMoreConfig.kt
@@ -13,4 +13,5 @@ object LearnMoreConfig {
     const val DEVICE_VERIFICATION_URL: String = "https://element.io/help#encryption-device-verification"
     const val SECURE_BACKUP_URL: String = "https://element.io/help#encryption5"
     const val IDENTITY_CHANGE_URL: String = "https://element.io/help#encryption18"
+    const val HISTORY_VISIBLE_URL: String = "https://element.io/en/help#e2ee-history-sharing"
 }
diff --git a/features/messages/impl/build.gradle.kts b/features/messages/impl/build.gradle.kts
index ad6562a83c..eb8aff66ed 100644
--- a/features/messages/impl/build.gradle.kts
+++ b/features/messages/impl/build.gradle.kts
@@ -68,6 +68,7 @@ dependencies {
     implementation(libs.jsoup)
     implementation(libs.androidx.constraintlayout)
     implementation(libs.androidx.constraintlayout.compose)
+    implementation(libs.androidx.datastore.preferences)
     implementation(libs.androidx.media3.exoplayer)
     implementation(libs.androidx.media3.ui)
     implementation(libs.sigpwned.emoji4j)
diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesPresenter.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesPresenter.kt
index e912722c6d..a5b3106b3d 100644
--- a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesPresenter.kt
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesPresenter.kt
@@ -32,6 +32,7 @@ import io.element.android.features.messages.api.timeline.HtmlConverterProvider
 import io.element.android.features.messages.impl.actionlist.ActionListEvents
 import io.element.android.features.messages.impl.actionlist.ActionListState
 import io.element.android.features.messages.impl.actionlist.model.TimelineItemAction
+import io.element.android.features.messages.impl.crypto.historyvisible.HistoryVisibleState
 import io.element.android.features.messages.impl.crypto.identity.IdentityChangeState
 import io.element.android.features.messages.impl.link.LinkState
 import io.element.android.features.messages.impl.messagecomposer.MessageComposerEvent
@@ -107,6 +108,7 @@ class MessagesPresenter(
     @Assisted private val timelinePresenter: Presenter<TimelineState>,
     private val timelineProtectionPresenter: Presenter<TimelineProtectionState>,
     private val identityChangeStatePresenter: Presenter<IdentityChangeState>,
+    private val historyVisibleStatePresenter: Presenter<HistoryVisibleState>,
     private val linkPresenter: Presenter<LinkState>,
     @Assisted private val actionListPresenter: Presenter<ActionListState>,
     private val customReactionPresenter: Presenter<CustomReactionState>,
@@ -158,6 +160,7 @@ class MessagesPresenter(
         val timelineState = timelinePresenter.present()
         val timelineProtectionState = timelineProtectionPresenter.present()
         val identityChangeState = identityChangeStatePresenter.present()
+        val historyVisibleState = historyVisibleStatePresenter.present()
         val actionListState = actionListPresenter.present()
         val linkState = linkPresenter.present()
         val customReactionState = customReactionPresenter.present()
@@ -278,6 +281,7 @@ class MessagesPresenter(
             timelineState = timelineState,
             timelineProtectionState = timelineProtectionState,
             identityChangeState = identityChangeState,
+            historyVisibleState = historyVisibleState,
             linkState = linkState,
             actionListState = actionListState,
             customReactionState = customReactionState,
diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesState.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesState.kt
index 9faf2f69eb..b9d86a6597 100644
--- a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesState.kt
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesState.kt
@@ -10,6 +10,7 @@ package io.element.android.features.messages.impl
 
 import io.element.android.features.messages.api.timeline.voicemessages.composer.VoiceMessageComposerState
 import io.element.android.features.messages.impl.actionlist.ActionListState
+import io.element.android.features.messages.impl.crypto.historyvisible.HistoryVisibleState
 import io.element.android.features.messages.impl.crypto.identity.IdentityChangeState
 import io.element.android.features.messages.impl.link.LinkState
 import io.element.android.features.messages.impl.messagecomposer.MessageComposerState
@@ -40,6 +41,7 @@ data class MessagesState(
     val timelineState: TimelineState,
     val timelineProtectionState: TimelineProtectionState,
     val identityChangeState: IdentityChangeState,
+    val historyVisibleState: HistoryVisibleState,
     val linkState: LinkState,
     val actionListState: ActionListState,
     val customReactionState: CustomReactionState,
diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesStateProvider.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesStateProvider.kt
index 3a077e6cf0..7831265fd0 100644
--- a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesStateProvider.kt
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesStateProvider.kt
@@ -14,7 +14,10 @@ import io.element.android.features.messages.api.timeline.voicemessages.composer.
 import io.element.android.features.messages.api.timeline.voicemessages.composer.aVoiceMessagePreviewState
 import io.element.android.features.messages.impl.actionlist.ActionListState
 import io.element.android.features.messages.impl.actionlist.anActionListState
+import io.element.android.features.messages.impl.crypto.historyvisible.HistoryVisibleState
+import io.element.android.features.messages.impl.crypto.historyvisible.aHistoryVisibleState
 import io.element.android.features.messages.impl.crypto.identity.IdentityChangeState
+import io.element.android.features.messages.impl.crypto.identity.aRoomMemberIdentityStateChange
 import io.element.android.features.messages.impl.crypto.identity.anIdentityChangeState
 import io.element.android.features.messages.impl.link.LinkState
 import io.element.android.features.messages.impl.link.aLinkState
@@ -48,6 +51,7 @@ import io.element.android.libraries.matrix.api.encryption.identity.IdentityState
 import io.element.android.libraries.matrix.api.room.tombstone.SuccessorRoom
 import io.element.android.libraries.matrix.api.timeline.Timeline
 import io.element.android.libraries.textcomposer.model.MessageComposerMode
+import io.element.android.libraries.textcomposer.model.aTextEditorStateMarkdown
 import io.element.android.libraries.textcomposer.model.aTextEditorStateRich
 import kotlinx.collections.immutable.ImmutableList
 import kotlinx.collections.immutable.persistentListOf
@@ -83,6 +87,19 @@ open class MessagesStateProvider : PreviewParameterProvider<MessagesState> {
                     timelineItems = aTimelineItemList(aTimelineItemTextContent()),
                 )
             ),
+            aMessagesState(
+                composerState = aMessageComposerState(textEditorState = aTextEditorStateMarkdown()),
+                identityChangeState = anIdentityChangeState(listOf(aRoomMemberIdentityStateChange()))
+            ),
+            aMessagesState(
+                composerState = aMessageComposerState(textEditorState = aTextEditorStateMarkdown()),
+                historyVisibleState = aHistoryVisibleState(showAlert = true)
+            ),
+            aMessagesState(
+                composerState = aMessageComposerState(textEditorState = aTextEditorStateMarkdown()),
+                identityChangeState = anIdentityChangeState(listOf(aRoomMemberIdentityStateChange())),
+                historyVisibleState = aHistoryVisibleState(showAlert = true)
+            )
         )
 }
 
@@ -103,6 +120,7 @@ fun aMessagesState(
     ),
     timelineProtectionState: TimelineProtectionState = aTimelineProtectionState(),
     identityChangeState: IdentityChangeState = anIdentityChangeState(),
+    historyVisibleState: HistoryVisibleState = aHistoryVisibleState(),
     linkState: LinkState = aLinkState(),
     readReceiptBottomSheetState: ReadReceiptBottomSheetState = aReadReceiptBottomSheetState(),
     actionListState: ActionListState = anActionListState(),
@@ -125,6 +143,7 @@ fun aMessagesState(
     voiceMessageComposerState = voiceMessageComposerState,
     timelineProtectionState = timelineProtectionState,
     identityChangeState = identityChangeState,
+    historyVisibleState = historyVisibleState,
     linkState = linkState,
     timelineState = timelineState,
     readReceiptBottomSheetState = readReceiptBottomSheetState,
diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesView.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesView.kt
index a37710843d..5479836bb3 100644
--- a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesView.kt
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesView.kt
@@ -53,6 +53,7 @@ import io.element.android.features.messages.api.timeline.voicemessages.composer.
 import io.element.android.features.messages.impl.actionlist.ActionListEvents
 import io.element.android.features.messages.impl.actionlist.ActionListView
 import io.element.android.features.messages.impl.actionlist.model.TimelineItemAction
+import io.element.android.features.messages.impl.crypto.historyvisible.HistoryVisibleStateView
 import io.element.android.features.messages.impl.crypto.identity.IdentityChangeStateView
 import io.element.android.features.messages.impl.link.LinkEvents
 import io.element.android.features.messages.impl.link.LinkView
@@ -486,10 +487,17 @@ private fun MessagesViewComposerBottomSheetContents(
                 // Do not show the identity change if user is composing a Rich message or is seeing suggestion(s).
                 if (state.composerState.suggestions.isEmpty() &&
                     state.composerState.textEditorState is TextEditorState.Markdown) {
-                    IdentityChangeStateView(
-                        state = state.identityChangeState,
-                        onLinkClick = onLinkClick,
-                    )
+                    if (state.identityChangeState.roomMemberIdentityStateChanges.isNotEmpty()) {
+                        IdentityChangeStateView(
+                            state = state.identityChangeState,
+                            onLinkClick = onLinkClick,
+                        )
+                    } else {
+                        HistoryVisibleStateView(
+                            state = state.historyVisibleState,
+                            onLinkClick = onLinkClick,
+                        )
+                    }
                 }
                 val verificationViolation = state.identityChangeState.roomMemberIdentityStateChanges.firstOrNull {
                     it.identityState == IdentityState.VerificationViolation
diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleAcknowledgementRepository.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleAcknowledgementRepository.kt
new file mode 100644
index 0000000000..1fa992fc3e
--- /dev/null
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleAcknowledgementRepository.kt
@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.messages.impl.crypto.historyvisible
+
+import androidx.datastore.preferences.core.booleanPreferencesKey
+import androidx.datastore.preferences.core.edit
+import dev.zacsweers.metro.ContributesBinding
+import io.element.android.libraries.androidutils.hash.hash
+import io.element.android.libraries.di.SessionScope
+import io.element.android.libraries.matrix.api.core.RoomId
+import io.element.android.libraries.matrix.api.core.SessionId
+import io.element.android.libraries.preferences.api.store.PreferenceDataStoreFactory
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.map
+
+interface HistoryVisibleAcknowledgementRepository {
+    fun hasAcknowledged(roomId: RoomId): Flow<Boolean>
+    suspend fun setAcknowledged(roomId: RoomId, value: Boolean)
+}
+
+@ContributesBinding(SessionScope::class)
+class DefaultHistoryVisibleAcknowledgementRepository(
+    sessionId: SessionId,
+    preferenceDataStoreFactory: PreferenceDataStoreFactory,
+) : HistoryVisibleAcknowledgementRepository {
+    val store =
+        sessionId.value.hash().take(16).let { hash ->
+            preferenceDataStoreFactory.create("elementx_historyvisible_$hash")
+        }
+
+    override fun hasAcknowledged(roomId: RoomId): Flow<Boolean> {
+        return store.data.map { prefs ->
+            val acknowledged = prefs[booleanPreferencesKey(roomId.value)] ?: false
+            acknowledged
+        }
+    }
+
+    override suspend fun setAcknowledged(roomId: RoomId, value: Boolean) {
+        store.edit { prefs ->
+            prefs[booleanPreferencesKey(roomId.value)] = value
+        }
+    }
+}
diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleEvent.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleEvent.kt
new file mode 100644
index 0000000000..775d9c00d4
--- /dev/null
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleEvent.kt
@@ -0,0 +1,12 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.messages.impl.crypto.historyvisible
+
+sealed interface HistoryVisibleEvent {
+    data object Acknowledge : HistoryVisibleEvent
+}
diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleState.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleState.kt
new file mode 100644
index 0000000000..3f980eb086
--- /dev/null
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleState.kt
@@ -0,0 +1,13 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.messages.impl.crypto.historyvisible
+
+data class HistoryVisibleState(
+    val showAlert: Boolean,
+    val eventSink: (HistoryVisibleEvent) -> Unit,
+)
diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleStatePresenter.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleStatePresenter.kt
new file mode 100644
index 0000000000..d76e567b3c
--- /dev/null
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleStatePresenter.kt
@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.messages.impl.crypto.historyvisible
+
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.rememberCoroutineScope
+import dev.zacsweers.metro.Inject
+import io.element.android.libraries.architecture.Presenter
+import io.element.android.libraries.featureflag.api.FeatureFlagService
+import io.element.android.libraries.featureflag.api.FeatureFlags
+import io.element.android.libraries.matrix.api.core.RoomId
+import io.element.android.libraries.matrix.api.room.JoinedRoom
+import io.element.android.libraries.matrix.api.room.history.RoomHistoryVisibility
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.coroutineScope
+import kotlinx.coroutines.launch
+
+@Inject
+class HistoryVisibleStatePresenter(
+    private val featureFlagService: FeatureFlagService,
+    private val repository: HistoryVisibleAcknowledgementRepository,
+    private val room: JoinedRoom,
+) : Presenter<HistoryVisibleState> {
+    @Composable
+    override fun present(): HistoryVisibleState {
+        val isFeatureEnabled by featureFlagService.isFeatureEnabledFlow(FeatureFlags.EnableKeyShareOnInvite).collectAsState(initial = false)
+        val roomInfo by room.roomInfoFlow.collectAsState()
+        // Implicitly assume the alert is initially acknowledged to avoid flashes in UI.
+        val acknowledged by repository.hasAcknowledged(room.roomId).collectAsState(initial = true)
+
+        val coroutineScope = rememberCoroutineScope()
+
+        LaunchedEffect(roomInfo.historyVisibility, acknowledged) {
+            if (roomInfo.historyVisibility == RoomHistoryVisibility.Joined && acknowledged) {
+                repository.setAcknowledged(room.roomId, false)
+            }
+        }
+
+        fun handleEvent(event: HistoryVisibleEvent) {
+            when (event) {
+                is HistoryVisibleEvent.Acknowledge -> coroutineScope.setAcknowledged(room.roomId, true)
+            }
+        }
+
+        return HistoryVisibleState(
+            showAlert = isFeatureEnabled && roomInfo.historyVisibility != RoomHistoryVisibility.Joined && roomInfo.isEncrypted == true && !acknowledged,
+            eventSink = ::handleEvent,
+        )
+    }
+
+    private fun CoroutineScope.setAcknowledged(roomId: RoomId, value: Boolean) = launch {
+        repository.setAcknowledged(roomId, value)
+    }
+}
diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleStateProvider.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleStateProvider.kt
new file mode 100644
index 0000000000..752abdc76b
--- /dev/null
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleStateProvider.kt
@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.messages.impl.crypto.historyvisible
+
+import androidx.compose.ui.tooling.preview.PreviewParameterProvider
+
+class HistoryVisibleStateProvider : PreviewParameterProvider<HistoryVisibleState> {
+    override val values: Sequence<HistoryVisibleState>
+    get() = sequenceOf(
+            aHistoryVisibleState(showAlert = true),
+        )
+}
+
+internal fun aHistoryVisibleState(
+    showAlert: Boolean = false,
+    eventSink: (HistoryVisibleEvent) -> Unit = {},
+) = HistoryVisibleState(
+    showAlert,
+    eventSink = eventSink,
+)
diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleStateView.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleStateView.kt
new file mode 100644
index 0000000000..9c08c9d101
--- /dev/null
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleStateView.kt
@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.messages.impl.crypto.historyvisible
+
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.LinkAnnotation
+import androidx.compose.ui.text.SpanStyle
+import androidx.compose.ui.text.buildAnnotatedString
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.style.TextDecoration
+import androidx.compose.ui.tooling.preview.PreviewParameter
+import io.element.android.appconfig.LearnMoreConfig
+import io.element.android.compound.theme.ElementTheme
+import io.element.android.libraries.designsystem.atomic.molecules.ComposerAlertLevel
+import io.element.android.libraries.designsystem.atomic.molecules.ComposerAlertMolecule
+import io.element.android.libraries.designsystem.preview.ElementPreview
+import io.element.android.libraries.designsystem.preview.PreviewsDayNight
+import io.element.android.libraries.ui.strings.CommonStrings
+
+@Composable
+fun HistoryVisibleStateView(
+    state: HistoryVisibleState,
+    onLinkClick: (String, Boolean) -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    if (!state.showAlert) {
+        return
+    }
+
+    ComposerAlertMolecule(
+        modifier = modifier,
+        avatar = null,
+        showIcon = true,
+        level = ComposerAlertLevel.Info,
+        content = buildAnnotatedString {
+            val learnMoreStr = stringResource(CommonStrings.action_learn_more)
+            val fullText = stringResource(CommonStrings.crypto_history_visible, learnMoreStr)
+            append(fullText)
+            val learnMoreStartIndex = fullText.lastIndexOf(learnMoreStr)
+            addStyle(
+                style = SpanStyle(
+                    textDecoration = TextDecoration.Underline,
+                    fontWeight = FontWeight.Bold,
+                    color = ElementTheme.colors.textPrimary
+                ),
+                start = learnMoreStartIndex,
+                end = learnMoreStartIndex + learnMoreStr.length,
+            )
+            addLink(
+                url = LinkAnnotation.Url(
+                    url = LearnMoreConfig.HISTORY_VISIBLE_URL,
+                    linkInteractionListener = {
+                        onLinkClick(LearnMoreConfig.HISTORY_VISIBLE_URL, true)
+                    }
+                ),
+                start = learnMoreStartIndex,
+                end = learnMoreStartIndex + learnMoreStr.length,
+            )
+        },
+        submitText = stringResource(CommonStrings.action_dismiss),
+        onSubmitClick = { state.eventSink(HistoryVisibleEvent.Acknowledge) },
+    )
+}
+
+@PreviewsDayNight
+@Composable
+internal fun HistoryVisibleStateViewPreview(
+    @PreviewParameter(HistoryVisibleStateProvider::class) state: HistoryVisibleState,
+) = ElementPreview {
+    HistoryVisibleStateView(
+        state = state,
+        onLinkClick = { _, _ -> },
+    )
+}
diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/MessagesViewWithHistoryVisiblePreview.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/MessagesViewWithHistoryVisiblePreview.kt
new file mode 100644
index 0000000000..07cf5170d3
--- /dev/null
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/MessagesViewWithHistoryVisiblePreview.kt
@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.messages.impl.crypto.historyvisible
+
+import androidx.compose.runtime.Composable
+import io.element.android.features.messages.impl.MessagesView
+import io.element.android.features.messages.impl.aMessagesState
+import io.element.android.features.messages.impl.messagecomposer.aMessageComposerState
+import io.element.android.libraries.designsystem.preview.ElementPreview
+import io.element.android.libraries.designsystem.preview.PreviewsDayNight
+import io.element.android.libraries.textcomposer.model.aTextEditorStateMarkdown
+
+@PreviewsDayNight
+@Composable
+internal fun MessagesViewWithHistoryVisiblePreview() = ElementPreview {
+    MessagesView(
+        state = aMessagesState(
+            composerState = aMessageComposerState(
+                textEditorState = aTextEditorStateMarkdown(
+                    initialText = "",
+                    initialFocus = false,
+                )
+            ),
+            historyVisibleState = aHistoryVisibleState(showAlert = true),
+        ),
+        onBackClick = {},
+        onRoomDetailsClick = {},
+        onEventContentClick = { _, _ -> false },
+        onUserDataClick = {},
+        onLinkClick = { _, _ -> },
+        onSendLocationClick = {},
+        onCreatePollClick = {},
+        onJoinCallClick = {},
+        onViewAllPinnedMessagesClick = {},
+        knockRequestsBannerView = {}
+    )
+}
diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/di/MessagesBindsModule.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/di/MessagesBindsModule.kt
index a345e09fa2..a88dbb1b49 100644
--- a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/di/MessagesBindsModule.kt
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/di/MessagesBindsModule.kt
@@ -11,6 +11,8 @@ package io.element.android.features.messages.impl.di
 import dev.zacsweers.metro.BindingContainer
 import dev.zacsweers.metro.Binds
 import dev.zacsweers.metro.ContributesTo
+import io.element.android.features.messages.impl.crypto.historyvisible.HistoryVisibleState
+import io.element.android.features.messages.impl.crypto.historyvisible.HistoryVisibleStatePresenter
 import io.element.android.features.messages.impl.crypto.identity.IdentityChangeState
 import io.element.android.features.messages.impl.crypto.identity.IdentityChangeStatePresenter
 import io.element.android.features.messages.impl.crypto.sendfailure.resolve.ResolveVerifiedUserSendFailurePresenter
@@ -61,4 +63,7 @@ interface MessagesBindsModule {
 
     @Binds
     fun bindIdentityChangeStatePresenter(presenter: IdentityChangeStatePresenter): Presenter<IdentityChangeState>
+
+    @Binds
+    fun bindHistoryVisibleStatePresenter(presenter: HistoryVisibleStatePresenter): Presenter<HistoryVisibleState>
 }
diff --git a/features/messages/impl/src/test/kotlin/io/element/android/features/messages/impl/MessagesPresenterTest.kt b/features/messages/impl/src/test/kotlin/io/element/android/features/messages/impl/MessagesPresenterTest.kt
index 852e2504b2..de2c8a81c9 100644
--- a/features/messages/impl/src/test/kotlin/io/element/android/features/messages/impl/MessagesPresenterTest.kt
+++ b/features/messages/impl/src/test/kotlin/io/element/android/features/messages/impl/MessagesPresenterTest.kt
@@ -17,6 +17,7 @@ import io.element.android.features.messages.impl.actionlist.ActionListEvents
 import io.element.android.features.messages.impl.actionlist.ActionListState
 import io.element.android.features.messages.impl.actionlist.anActionListState
 import io.element.android.features.messages.impl.actionlist.model.TimelineItemAction
+import io.element.android.features.messages.impl.crypto.historyvisible.aHistoryVisibleState
 import io.element.android.features.messages.impl.crypto.identity.anIdentityChangeState
 import io.element.android.features.messages.impl.fixtures.aMessageEvent
 import io.element.android.features.messages.impl.link.aLinkState
@@ -1355,6 +1356,7 @@ class MessagesPresenterTest {
             timelinePresenter = { aTimelineState(eventSink = timelineEventSink) },
             timelineProtectionPresenter = { aTimelineProtectionState() },
             identityChangeStatePresenter = { anIdentityChangeState() },
+            historyVisibleStatePresenter = { aHistoryVisibleState() },
             linkPresenter = { aLinkState() },
             actionListPresenter = { anActionListState(eventSink = actionListEventSink) },
             customReactionPresenter = { aCustomReactionState() },
diff --git a/features/messages/impl/src/test/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/FakeHistoryVisibleAcknowledgementRepository.kt b/features/messages/impl/src/test/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/FakeHistoryVisibleAcknowledgementRepository.kt
new file mode 100644
index 0000000000..faf21720fa
--- /dev/null
+++ b/features/messages/impl/src/test/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/FakeHistoryVisibleAcknowledgementRepository.kt
@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.messages.impl.crypto.historyvisible
+
+import io.element.android.libraries.matrix.api.core.RoomId
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableStateFlow
+
+class FakeHistoryVisibleAcknowledgementRepository(
+    private val acknowledgements: MutableMap<RoomId, MutableStateFlow<Boolean>> = mutableMapOf()
+) : HistoryVisibleAcknowledgementRepository {
+    override fun hasAcknowledged(roomId: RoomId): Flow<Boolean> {
+        return acknowledgements.getOrPut(roomId) {
+            MutableStateFlow(false)
+        }
+    }
+
+    override suspend fun setAcknowledged(roomId: RoomId, value: Boolean) {
+        val flow = acknowledgements.getOrPut(roomId) {
+            MutableStateFlow(value)
+        }
+        flow.emit(value)
+    }
+
+    companion object {
+        /**
+         * Create the repository with a pre-existing entry.
+         */
+        fun withRoom(roomId: RoomId, acknowledged: Boolean = false): FakeHistoryVisibleAcknowledgementRepository {
+            return FakeHistoryVisibleAcknowledgementRepository(
+                mutableMapOf(
+                    roomId to MutableStateFlow(acknowledged)
+                )
+            )
+        }
+    }
+}
diff --git a/features/messages/impl/src/test/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleStatePresenterTest.kt b/features/messages/impl/src/test/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleStatePresenterTest.kt
new file mode 100644
index 0000000000..b6619851e6
--- /dev/null
+++ b/features/messages/impl/src/test/kotlin/io/element/android/features/messages/impl/crypto/historyvisible/HistoryVisibleStatePresenterTest.kt
@@ -0,0 +1,127 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.messages.impl.crypto.historyvisible
+
+import com.google.common.truth.Truth.assertThat
+import io.element.android.libraries.featureflag.api.FeatureFlags
+import io.element.android.libraries.featureflag.test.FakeFeatureFlagService
+import io.element.android.libraries.matrix.api.room.JoinedRoom
+import io.element.android.libraries.matrix.api.room.history.RoomHistoryVisibility
+import io.element.android.libraries.matrix.test.room.FakeJoinedRoom
+import io.element.android.libraries.matrix.test.room.aRoomInfo
+import io.element.android.tests.testutils.WarmUpRule
+import io.element.android.tests.testutils.awaitLastSequentialItem
+import io.element.android.tests.testutils.test
+import kotlinx.coroutines.test.runTest
+import org.junit.Rule
+import org.junit.Test
+
+class HistoryVisibleStatePresenterTest {
+    @get:Rule
+    val warmUpRule = WarmUpRule()
+
+    @Test
+    fun `present - not visible if feature disabled`() = runTest {
+        val room = FakeJoinedRoom()
+        room.givenRoomInfo(aRoomInfo(historyVisibility = RoomHistoryVisibility.Joined, isEncrypted = true))
+        val presenter = createHistoryVisibleStatePresenter(room, enabled = false, acknowledged = false)
+        presenter.test {
+            assertThat(awaitLastSequentialItem().showAlert).isFalse()
+        }
+    }
+
+    @Test
+    fun `present - initial with room shared, unencrypted`() = runTest {
+        val room = FakeJoinedRoom()
+        room.givenRoomInfo(aRoomInfo(historyVisibility = RoomHistoryVisibility.Shared, isEncrypted = false))
+        val presenter = createHistoryVisibleStatePresenter(room)
+        presenter.test {
+            assertThat(awaitLastSequentialItem().showAlert).isFalse()
+        }
+    }
+
+    @Test
+    fun `present - initial with room joined, encrypted`() = runTest {
+        val room = FakeJoinedRoom()
+        room.givenRoomInfo(aRoomInfo(historyVisibility = RoomHistoryVisibility.Joined, isEncrypted = false))
+        val presenter = createHistoryVisibleStatePresenter(room)
+        presenter.test {
+            assertThat(awaitLastSequentialItem().showAlert).isFalse()
+        }
+    }
+
+    @Test
+    fun `present - initial with room shared, encrypted, unacknowledged`() = runTest {
+        val room = FakeJoinedRoom()
+        room.givenRoomInfo(aRoomInfo(historyVisibility = RoomHistoryVisibility.Shared, isEncrypted = true))
+        val presenter = createHistoryVisibleStatePresenter(room, acknowledged = false)
+        presenter.test {
+            val initialState = awaitItem()
+            assertThat(initialState.showAlert).isFalse()
+            val nextState = awaitItem()
+            assertThat(nextState.showAlert).isTrue()
+        }
+    }
+
+    @Test
+    fun `present - initial with room shared, encrypted, acknowledged`() = runTest {
+        val room = FakeJoinedRoom()
+        room.givenRoomInfo(aRoomInfo(historyVisibility = RoomHistoryVisibility.Shared, isEncrypted = true))
+        val presenter = createHistoryVisibleStatePresenter(room, acknowledged = true)
+        presenter.test {
+            assertThat(awaitLastSequentialItem().showAlert).isFalse()
+        }
+    }
+
+    @Test
+    fun `present - transition from joined + unencrypted, to shared + encrypted`() = runTest {
+        val room = FakeJoinedRoom()
+        val featureFlagService = FakeFeatureFlagService(mapOf(FeatureFlags.EnableKeyShareOnInvite.key to true))
+        val repository = FakeHistoryVisibleAcknowledgementRepository()
+
+        room.givenRoomInfo(aRoomInfo(historyVisibility = RoomHistoryVisibility.Joined, isEncrypted = false))
+
+        val presenter = HistoryVisibleStatePresenter(
+            featureFlagService,
+            repository,
+            room,
+        )
+
+        presenter.test {
+            // emitted by the feature flag service(?)
+            assertThat(awaitItem().showAlert).isFalse()
+
+            // emitted state from room info assignment
+            assertThat(awaitItem().showAlert).isFalse()
+
+            // room is marked as encrypted
+            room.givenRoomInfo(aRoomInfo(historyVisibility = RoomHistoryVisibility.Joined, isEncrypted = true))
+            assertThat(awaitItem().showAlert).isFalse()
+
+            // room history visibility is changed to shared
+            room.givenRoomInfo(aRoomInfo(historyVisibility = RoomHistoryVisibility.Shared, isEncrypted = true))
+            assertThat(awaitItem().showAlert).isTrue()
+
+            // alert is acknowledged
+            repository.setAcknowledged(room.roomId, true)
+            assertThat(awaitItem().showAlert).isFalse()
+        }
+    }
+
+    private fun createHistoryVisibleStatePresenter(
+        room: JoinedRoom = FakeJoinedRoom(),
+        enabled: Boolean = true,
+        acknowledged: Boolean = false
+    ): HistoryVisibleStatePresenter {
+        return HistoryVisibleStatePresenter(
+            room = room,
+            featureFlagService = FakeFeatureFlagService(mapOf("feature.enableKeyShareOnInvite" to enabled)),
+            repository = FakeHistoryVisibleAcknowledgementRepository.withRoom(room.roomId, acknowledged)
+        )
+    }
+}
diff --git a/tests/konsist/src/test/kotlin/io/element/android/tests/konsist/KonsistPreviewTest.kt b/tests/konsist/src/test/kotlin/io/element/android/tests/konsist/KonsistPreviewTest.kt
index b4f15d8d96..32f2908cf7 100644
--- a/tests/konsist/src/test/kotlin/io/element/android/tests/konsist/KonsistPreviewTest.kt
+++ b/tests/konsist/src/test/kotlin/io/element/android/tests/konsist/KonsistPreviewTest.kt
@@ -97,6 +97,7 @@ class KonsistPreviewTest {
         "MessageComposerViewVoicePreview",
         "MessagesReactionButtonAddPreview",
         "MessagesReactionButtonExtraPreview",
+        "MessagesViewWithHistoryVisiblePreview",
         "MessagesViewWithIdentityChangePreview",
         "PendingMemberRowWithLongNamePreview",
         "PinUnlockViewInAppPreview",
diff --git a/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_HistoryVisibleStateView_Day_0_en.png b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_HistoryVisibleStateView_Day_0_en.png
new file mode 100644
index 0000000000..d19a140456
--- /dev/null
+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_HistoryVisibleStateView_Day_0_en.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:96bc0c555188cee4b3f3e3e0f28f944a4225e27b9a1069edf2b10a2993ee3080
+size 26078
diff --git a/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_HistoryVisibleStateView_Day_1_en.png b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_HistoryVisibleStateView_Day_1_en.png
new file mode 100644
index 0000000000..d19a140456
--- /dev/null
+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_HistoryVisibleStateView_Day_1_en.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:96bc0c555188cee4b3f3e3e0f28f944a4225e27b9a1069edf2b10a2993ee3080
+size 26078
diff --git a/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_HistoryVisibleStateView_Night_0_en.png b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_HistoryVisibleStateView_Night_0_en.png
new file mode 100644
index 0000000000..d21a12dd64
--- /dev/null
+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_HistoryVisibleStateView_Night_0_en.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:a103daf8447cb571a0c5010d062a7790aaa0f3dce30f052bf86884708f4881a5
+size 28769
diff --git a/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_HistoryVisibleStateView_Night_1_en.png b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_HistoryVisibleStateView_Night_1_en.png
new file mode 100644
index 0000000000..d21a12dd64
--- /dev/null
+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_HistoryVisibleStateView_Night_1_en.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:a103daf8447cb571a0c5010d062a7790aaa0f3dce30f052bf86884708f4881a5
+size 28769
diff --git a/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_MessagesViewWithHistoryVisible_Day_0_en.png b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_MessagesViewWithHistoryVisible_Day_0_en.png
new file mode 100644
index 0000000000..22d05e61fa
--- /dev/null
+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_MessagesViewWithHistoryVisible_Day_0_en.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:9682cdd7e08e32591fa47f56da5e6ef4cc3a777700931c2c86e9b802a9cf25cb
+size 67342
diff --git a/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_MessagesViewWithHistoryVisible_Day_1_en.png b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_MessagesViewWithHistoryVisible_Day_1_en.png
new file mode 100644
index 0000000000..22d05e61fa
--- /dev/null
+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_MessagesViewWithHistoryVisible_Day_1_en.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:9682cdd7e08e32591fa47f56da5e6ef4cc3a777700931c2c86e9b802a9cf25cb
+size 67342
diff --git a/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_MessagesViewWithHistoryVisible_Night_0_en.png b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_MessagesViewWithHistoryVisible_Night_0_en.png
new file mode 100644
index 0000000000..b2bb8ac3fc
--- /dev/null
+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_MessagesViewWithHistoryVisible_Night_0_en.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
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+size 69457
diff --git a/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_MessagesViewWithHistoryVisible_Night_1_en.png b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_MessagesViewWithHistoryVisible_Night_1_en.png
new file mode 100644
index 0000000000..b2bb8ac3fc
--- /dev/null
+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl.crypto.historyvisible_MessagesViewWithHistoryVisible_Night_1_en.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
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+size 69457
diff --git a/tests/uitests/src/test/snapshots/images/features.messages.impl_MessagesView_Day_10_en.png b/tests/uitests/src/test/snapshots/images/features.messages.impl_MessagesView_Day_10_en.png
new file mode 100644
index 0000000000..826ba15d61
--- /dev/null
+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl_MessagesView_Day_10_en.png
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
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+size 66428
diff --git a/tests/uitests/src/test/snapshots/images/features.messages.impl_MessagesView_Day_11_en.png b/tests/uitests/src/test/snapshots/images/features.messages.impl_MessagesView_Day_11_en.png
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index 0000000000..ca2c69a01b
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+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl_MessagesView_Day_11_en.png
@@ -0,0 +1,3 @@
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--- /dev/null
+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl_MessagesView_Day_12_en.png
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--- /dev/null
+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl_MessagesView_Night_10_en.png
@@ -0,0 +1,3 @@
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--- /dev/null
+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl_MessagesView_Night_11_en.png
@@ -0,0 +1,3 @@
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+++ b/tests/uitests/src/test/snapshots/images/features.messages.impl_MessagesView_Night_12_en.png
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