diff --git a/Telegram/SourceFiles/data/data_sparse_ids.h b/Telegram/SourceFiles/data/data_sparse_ids.h
index 6cd5b9f29..264358032 100644
--- a/Telegram/SourceFiles/data/data_sparse_ids.h
+++ b/Telegram/SourceFiles/data/data_sparse_ids.h
@@ -79,6 +79,9 @@ public:
 				&& (migratedPeerId == other.migratedPeerId)
 				&& (universalId == other.universalId);
 		}
+		bool operator!=(const Key &other) const {
+			return !(*this == other);
+		}
 
 		PeerId peerId = 0;
 		PeerId migratedPeerId = 0;
diff --git a/Telegram/SourceFiles/facades.cpp b/Telegram/SourceFiles/facades.cpp
index f92e6a6ef..e1ca65e65 100644
--- a/Telegram/SourceFiles/facades.cpp
+++ b/Telegram/SourceFiles/facades.cpp
@@ -36,6 +36,7 @@ Copyright (c) 2014-2017 John Preston, https://desktop.telegram.org
 #include "base/observer.h"
 #include "base/task_queue.h"
 #include "history/history_media.h"
+#include "styles/style_history.h"
 
 Q_DECLARE_METATYPE(ClickHandlerPtr);
 Q_DECLARE_METATYPE(Qt::MouseButton);
@@ -359,15 +360,25 @@ void handlePendingHistoryUpdate() {
 	}
 	Auth().data().pendingHistoryResize().notify(true);
 
-	for (auto item : base::take(Global::RefPendingRepaintItems())) {
+	for (const auto item : base::take(Global::RefPendingRepaintItems())) {
 		Auth().data().requestItemRepaint(item);
 
 		// Start the video if it is waiting for that.
 		if (item->pendingInitDimensions()) {
-			if (auto media = item->getMedia()) {
-				if (auto reader = media->getClipReader()) {
-					if (!reader->started() && reader->mode() == Media::Clip::Reader::Mode::Video) {
-						item->resizeGetHeight(item->width());
+			if (const auto media = item->getMedia()) {
+				if (const auto reader = media->getClipReader()) {
+					const auto startRequired = [&] {
+						if (reader->started()) {
+							return false;
+						}
+						using Mode = Media::Clip::Reader::Mode;
+						return (reader->mode() == Mode::Video);
+					};
+					if (startRequired()) {
+						const auto width = std::max(
+							item->width(),
+							st::historyMinimalWidth);
+						item->resizeGetHeight(width);
 					}
 				}
 			}
diff --git a/Telegram/SourceFiles/history/history_item.cpp b/Telegram/SourceFiles/history/history_item.cpp
index 2f8b3ab14..a6fd4f499 100644
--- a/Telegram/SourceFiles/history/history_item.cpp
+++ b/Telegram/SourceFiles/history/history_item.cpp
@@ -1148,6 +1148,11 @@ void HistoryItem::clipCallback(Media::Clip::Notification notification) {
 		}
 		if (!stopped) {
 			setPendingInitDimensions();
+			if (detached()) {
+				// We still want to handle our pending initDimensions and
+				// resize state even if we're detached in history.
+				_history->setHasPendingResizedItems();
+			}
 			Auth().data().markItemLayoutChanged(this);
 			Global::RefPendingRepaintItems().insert(this);
 		}
diff --git a/Telegram/SourceFiles/history/history_media_types.cpp b/Telegram/SourceFiles/history/history_media_types.cpp
index ebf3d0983..e69043e27 100644
--- a/Telegram/SourceFiles/history/history_media_types.cpp
+++ b/Telegram/SourceFiles/history/history_media_types.cpp
@@ -1052,7 +1052,10 @@ HistoryDocument::HistoryDocument(not_null<HistoryItem*> parent, DocumentData *do
 	}
 }
 
-HistoryDocument::HistoryDocument(not_null<HistoryItem*> parent, const HistoryDocument &other) : HistoryFileMedia(parent)
+HistoryDocument::HistoryDocument(
+	not_null<HistoryItem*> parent,
+	const HistoryDocument &other)
+: HistoryFileMedia(parent)
 , RuntimeComposer()
 , _data(other._data) {
 	auto captioned = other.Get<HistoryDocumentCaptioned>();
diff --git a/Telegram/SourceFiles/media/player/media_player_instance.cpp b/Telegram/SourceFiles/media/player/media_player_instance.cpp
index b3ab6eaa4..5e2e2c1d5 100644
--- a/Telegram/SourceFiles/media/player/media_player_instance.cpp
+++ b/Telegram/SourceFiles/media/player/media_player_instance.cpp
@@ -34,6 +34,12 @@ namespace {
 
 Instance *SingleInstance = nullptr;
 
+// Preload X message ids before and after current.
+constexpr auto kIdsLimit = 32;
+
+// Preload next messages if we went further from current than that.
+constexpr auto kIdsPreloadAfter = 28;
+
 } // namespace
 
 void start() {
@@ -113,55 +119,162 @@ void Instance::setCurrent(const AudioMsgId &audioId) {
 				data->migrated = nullptr;
 			}
 			_trackChangedNotifier.notify(data->type, true);
-			if (data->history != history || data->migrated != migrated) {
-				rebuildPlaylist(data);
-			}
+			refreshPlaylist(data);
 		}
 	}
 }
 
-void Instance::rebuildPlaylist(not_null<Data*> data) {
-	// #TODO playlist
+void Instance::refreshPlaylist(not_null<Data*> data) {
+	if (!validPlaylist(data)) {
+		validatePlaylist(data);
+	}
+	playlistUpdated(data);
+}
+
+void Instance::playlistUpdated(not_null<Data*> data) {
+	if (data->playlistSlice) {
+		const auto fullId = data->current.contextId();
+		data->playlistIndex = data->playlistSlice->indexOf(fullId);
+	} else {
+		data->playlistIndex = base::none;
+	}
+	data->playlistChanges.fire({});
+}
+
+bool Instance::validPlaylist(not_null<Data*> data) {
+	if (const auto key = playlistKey(data)) {
+		if (!data->playlistSlice) {
+			return false;
+		}
+		using Key = SliceKey;
+		const auto inSameDomain = [](const Key &a, const Key &b) {
+			return (a.peerId == b.peerId)
+				&& (a.migratedPeerId == b.migratedPeerId);
+		};
+		const auto countDistanceInData = [&](const Key &a, const Key &b) {
+			return [&](const SparseIdsMergedSlice &data) {
+				return inSameDomain(a, b)
+					? data.distance(a, b)
+					: base::optional<int>();
+			};
+		};
+
+		if (key == data->playlistRequestedKey) {
+			return true;
+		} else if (!data->playlistSliceKey
+			|| !data->playlistRequestedKey
+			|| *data->playlistRequestedKey != *data->playlistSliceKey) {
+			return false;
+		}
+		auto distance = data->playlistSlice
+			| countDistanceInData(*key, *data->playlistRequestedKey)
+			| func::abs;
+		if (distance) {
+			return (*distance < kIdsPreloadAfter);
+		}
+	}
+	return !data->playlistSlice;
+}
+
+void Instance::validatePlaylist(not_null<Data*> data) {
+	if (const auto key = playlistKey(data)) {
+		data->playlistRequestedKey = key;
+		SharedMediaMergedViewer(
+			SharedMediaMergedKey(*key, data->overview),
+			kIdsLimit,
+			kIdsLimit
+		) | rpl::start_with_next([=](SparseIdsMergedSlice &&update) {
+			data->playlistSlice = std::move(update);
+			data->playlistSliceKey = key;
+			playlistUpdated(data);
+		}, data->playlistLifetime);
+	} else {
+		data->playlistSlice = base::none;
+		data->playlistSliceKey = data->playlistRequestedKey = base::none;
+		playlistUpdated(data);
+	}
+}
+
+auto Instance::playlistKey(not_null<Data*> data) const
+-> base::optional<SliceKey> {
+	const auto contextId = data->current.contextId();
+	const auto history = data->history;
+	if (!contextId || !history) {
+		return {};
+	}
+
+	const auto universalId = (contextId.channel == history->channelId())
+		? contextId.msg
+		: (contextId.msg - ServerMaxMsgId);
+	return SliceKey(
+		data->history->peer->id,
+		data->migrated ? data->migrated->peer->id : 0,
+		universalId);
+}
+
+HistoryItem *Instance::itemByIndex(not_null<Data*> data, int index) {
+	if (!data->playlistSlice
+		|| index < 0
+		|| index >= data->playlistSlice->size()) {
+		return nullptr;
+	}
+	const auto fullId = (*data->playlistSlice)[index];
+	return App::histItemById(fullId);
 }
 
 bool Instance::moveInPlaylist(
 		not_null<Data*> data,
 		int delta,
 		bool autonext) {
-	//auto index = data->playlist.indexOf(data->current.contextId());
-	//auto newIndex = index + delta;
-	//if (!data->current || index < 0 || newIndex < 0 || newIndex >= data->playlist.size()) {
-	//	rebuildPlaylist(data);
-	//	return false;
-	//}
-
-	//auto msgId = data->playlist[newIndex];
-	//if (auto item = App::histItemById(msgId)) {
-	//	if (auto media = item->getMedia()) {
-	//		if (auto document = media->getDocument()) {
-	//			if (autonext) {
-	//				_switchToNextNotifier.notify({ data->current, msgId });
-	//			}
-	//			DocumentOpenClickHandler::doOpen(media->getDocument(), item, ActionOnLoadPlayInline);
-	//			return true;
-	//		}
-	//	}
-	//}
-	//return false;
+	if (!data->playlistIndex) {
+		return false;
+	}
+	const auto newIndex = *data->playlistIndex + delta;
+	if (const auto item = itemByIndex(data, newIndex)) {
+		if (const auto media = item->getMedia()) {
+			if (const auto document = media->getDocument()) {
+				if (autonext) {
+					_switchToNextNotifier.notify({
+						data->current,
+						item->fullId()
+					});
+				}
+				if (document->tryPlaySong()) {
+					play(AudioMsgId(document, item->fullId()));
+				} else {
+					DocumentOpenClickHandler::doOpen(
+						document,
+						item,
+						ActionOnLoadPlayInline);
+				}
+				return true;
+			}
+		}
+	}
 	return false;
 }
 
 bool Instance::previousAvailable(AudioMsgId::Type type) const {
-	return false;
+	const auto data = getData(type);
+	Assert(data != nullptr);
+	return data->playlistIndex
+		&& data->playlistSlice
+		&& (*data->playlistIndex > 0);
 }
 
 bool Instance::nextAvailable(AudioMsgId::Type type) const {
-	return false;
+	const auto data = getData(type);
+	Assert(data != nullptr);
+	return data->playlistIndex
+		&& data->playlistSlice
+		&& (*data->playlistIndex + 1 < data->playlistSlice->size());
 }
 
 rpl::producer<> Media::Player::Instance::playlistChanges(
 		AudioMsgId::Type type) const {
-	return rpl::never<>();
+	const auto data = getData(type);
+	Assert(data != nullptr);
+	return data->playlistChanges.events();
 }
 
 Instance *instance() {
@@ -188,7 +301,7 @@ void Instance::play(const AudioMsgId &audioId) {
 	if (!audioId) {
 		return;
 	}
-	if (audioId.audio()->song() || audioId.audio()->voice()) {
+	if (audioId.audio()->tryPlaySong() || audioId.audio()->voice()) {
 		mixer()->play(audioId);
 		setCurrent(audioId);
 		if (audioId.audio()->loading()) {
@@ -282,7 +395,10 @@ void Instance::stopSeeking(AudioMsgId::Type type) {
 }
 
 void Instance::documentLoadProgress(DocumentData *document) {
-	emitUpdate(document->song() ? AudioMsgId::Type::Song : AudioMsgId::Type::Voice, [document](const AudioMsgId &audioId) {
+	const auto type = document->tryPlaySong()
+		? AudioMsgId::Type::Song
+		: AudioMsgId::Type::Voice;
+	emitUpdate(type, [document](const AudioMsgId &audioId) {
 		return (audioId.audio() == document);
 	});
 }
@@ -316,26 +432,24 @@ void Instance::emitUpdate(AudioMsgId::Type type, CheckCallback check) {
 }
 
 void Instance::preloadNext(not_null<Data*> data) {
-	if (!data->current) {
+	if (!data->current || !data->playlistSlice || !data->playlistIndex) {
 		return;
 	}
-	//auto index = data->playlist.indexOf(data->current.contextId());
-	//if (index < 0) {
-	//	return;
-	//}
-	//auto nextIndex = index + 1;
-	//if (nextIndex >= data->playlist.size()) {
-	//	return;
-	//}
-	//if (auto item = App::histItemById(data->playlist[nextIndex])) {
-	//	if (auto media = item->getMedia()) {
-	//		if (auto document = media->getDocument()) {
-	//			if (!document->loaded(DocumentData::FilePathResolveSaveFromDataSilent)) {
-	//				DocumentOpenClickHandler::doOpen(document, nullptr, ActionOnLoadNone);
-	//			}
-	//		}
-	//	}
-	//}
+	const auto nextIndex = *data->playlistIndex + 1;
+	if (const auto item = itemByIndex(data, nextIndex)) {
+		if (const auto media = item->getMedia()) {
+			if (const auto document = media->getDocument()) {
+				const auto isLoaded = document->loaded(
+					DocumentData::FilePathResolveSaveFromDataSilent);
+				if (!isLoaded) {
+					DocumentOpenClickHandler::doOpen(
+						document,
+						nullptr,
+						ActionOnLoadNone);
+				}
+			}
+		}
+	}
 }
 
 void Instance::handleLogout() {
diff --git a/Telegram/SourceFiles/media/player/media_player_instance.h b/Telegram/SourceFiles/media/player/media_player_instance.h
index 4f32dd12c..f87fe9ba9 100644
--- a/Telegram/SourceFiles/media/player/media_player_instance.h
+++ b/Telegram/SourceFiles/media/player/media_player_instance.h
@@ -141,6 +141,7 @@ private:
 	friend void start();
 
 	using SharedMediaType = Storage::SharedMediaType;
+	using SliceKey = SparseIdsMergedSlice::Key;
 	struct Data {
 		Data(AudioMsgId::Type type, SharedMediaType overview)
 		: type(type)
@@ -152,6 +153,11 @@ private:
 		AudioMsgId current;
 		AudioMsgId seeking;
 		base::optional<SparseIdsMergedSlice> playlistSlice;
+		base::optional<SliceKey> playlistSliceKey;
+		base::optional<SliceKey> playlistRequestedKey;
+		base::optional<int> playlistIndex;
+		rpl::lifetime playlistLifetime;
+		rpl::event_stream<> playlistChanges;
 		History *history = nullptr;
 		History *migrated = nullptr;
 		bool repeatEnabled = false;
@@ -162,9 +168,14 @@ private:
 	void handleSongUpdate(const AudioMsgId &audioId);
 
 	void setCurrent(const AudioMsgId &audioId);
-	void rebuildPlaylist(not_null<Data*> data);
+	void refreshPlaylist(not_null<Data*> data);
+	base::optional<SliceKey> playlistKey(not_null<Data*> data) const;
+	bool validPlaylist(not_null<Data*> data);
+	void validatePlaylist(not_null<Data*> data);
+	void playlistUpdated(not_null<Data*> data);
 	bool moveInPlaylist(not_null<Data*> data, int delta, bool autonext);
 	void preloadNext(not_null<Data*> data);
+	HistoryItem *itemByIndex(not_null<Data*> data, int index);
 	void handleLogout();
 
 	template <typename CheckCallback>
diff --git a/Telegram/SourceFiles/mediaview.cpp b/Telegram/SourceFiles/mediaview.cpp
index 1c578c95d..cf7f76884 100644
--- a/Telegram/SourceFiles/mediaview.cpp
+++ b/Telegram/SourceFiles/mediaview.cpp
@@ -2316,12 +2316,12 @@ void MediaView::setContext(base::optional_variant<
 	_user = _peer ? _peer->asUser() : nullptr;
 }
 
-bool MediaView::moveToNext(int32 delta) {
+bool MediaView::moveToNext(int delta) {
 	if (!_index) {
 		return false;
 	}
 	auto newIndex = *_index + delta;
-	auto entity = entityByIndex(*_index + delta);
+	auto entity = entityByIndex(newIndex);
 	if (!entity.data && !entity.item) {
 		return false;
 	}
@@ -2345,7 +2345,7 @@ bool MediaView::moveToNext(int32 delta) {
 	return true;
 }
 
-void MediaView::preloadData(int32 delta) {
+void MediaView::preloadData(int delta) {
 	if (!_index) {
 		return;
 	}
diff --git a/Telegram/SourceFiles/mediaview.h b/Telegram/SourceFiles/mediaview.h
index be131318c..fc78146f2 100644
--- a/Telegram/SourceFiles/mediaview.h
+++ b/Telegram/SourceFiles/mediaview.h
@@ -147,8 +147,8 @@ private:
 
 	void updateOver(QPoint mpos);
 	void moveToScreen();
-	bool moveToNext(int32 delta);
-	void preloadData(int32 delta);
+	bool moveToNext(int delta);
+	void preloadData(int delta);
 	struct Entity {
 		base::optional_variant<
 			not_null<PhotoData*>,