diff --git a/Telegram/SourceFiles/apiwrap.cpp b/Telegram/SourceFiles/apiwrap.cpp
index 0a0df1e1f0..c4a5eb26f7 100644
--- a/Telegram/SourceFiles/apiwrap.cpp
+++ b/Telegram/SourceFiles/apiwrap.cpp
@@ -2896,8 +2896,12 @@ void ApiWrap::refreshFileReference(
 			MTPmessages_GetSavedGifs(MTP_int(0)),
 			[=] { crl::on_main(_session, [=] { local().writeSavedGifs(); }); });
 	}, [&](Data::FileOriginWallpaper data) {
-		request(MTPaccount_GetWallPaper(
-			MTP_inputWallPaper(
+		const auto useSlug = data.ownerId
+			&& (data.ownerId != session().userId())
+			&& !data.slug.isEmpty();
+		request(MTPaccount_GetWallPaper(useSlug
+			? MTP_inputWallPaperSlug(MTP_string(data.slug))
+			: MTP_inputWallPaper(
 				MTP_long(data.paperId),
 				MTP_long(data.accessHash))));
 	}, [&](Data::FileOriginTheme data) {
diff --git a/Telegram/SourceFiles/boxes/background_box.cpp b/Telegram/SourceFiles/boxes/background_box.cpp
index 9ead668bb8..7f47d003a4 100644
--- a/Telegram/SourceFiles/boxes/background_box.cpp
+++ b/Telegram/SourceFiles/boxes/background_box.cpp
@@ -174,7 +174,7 @@ void BackgroundBox::removePaper(const Data::WallPaper &paper) {
 		}
 		session->data().removeWallpaper(paper);
 		session->api().request(MTPaccount_SaveWallPaper(
-			paper.mtpInput(),
+			paper.mtpInput(session),
 			MTP_bool(true),
 			paper.mtpSettings()
 		)).send();
diff --git a/Telegram/SourceFiles/boxes/background_preview_box.cpp b/Telegram/SourceFiles/boxes/background_preview_box.cpp
index 4d0a4c9937..fd63f3891e 100644
--- a/Telegram/SourceFiles/boxes/background_preview_box.cpp
+++ b/Telegram/SourceFiles/boxes/background_preview_box.cpp
@@ -506,7 +506,7 @@ void BackgroundPreviewBox::apply() {
 	_controller->content()->setChatBackground(_paper, std::move(_full));
 	if (install) {
 		_controller->session().api().request(MTPaccount_InstallWallPaper(
-			_paper.mtpInput(),
+			_paper.mtpInput(&_controller->session()),
 			_paper.mtpSettings()
 		)).send();
 	}
diff --git a/Telegram/SourceFiles/core/core_settings.cpp b/Telegram/SourceFiles/core/core_settings.cpp
index 64c113fbe0..9305a5cc5a 100644
--- a/Telegram/SourceFiles/core/core_settings.cpp
+++ b/Telegram/SourceFiles/core/core_settings.cpp
@@ -10,6 +10,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "boxes/send_files_box.h"
 #include "ui/widgets/input_fields.h"
 #include "storage/serialize_common.h"
+#include "window/themes/window_theme.h"
 #include "facades.h"
 
 namespace Core {
@@ -87,8 +88,9 @@ QByteArray Settings::serialize() const {
 			stream << quint64(i);
 		}
 		stream
-			<< qint32(_autoDownloadDictionaries.current() ? 1 : 0);
-
+			<< qint32(_autoDownloadDictionaries.current() ? 1 : 0)
+			<< qint32(Window::Theme::Background()->tileDay() ? 1 : 0)
+			<< qint32(Window::Theme::Background()->tileNight() ? 1 : 0);
 	}
 	return result;
 }
diff --git a/Telegram/SourceFiles/data/data_file_origin.h b/Telegram/SourceFiles/data/data_file_origin.h
index 6c8a0d5f7c..60936abe79 100644
--- a/Telegram/SourceFiles/data/data_file_origin.h
+++ b/Telegram/SourceFiles/data/data_file_origin.h
@@ -61,13 +61,21 @@ struct FileOriginSavedGifs {
 };
 
 struct FileOriginWallpaper {
-	FileOriginWallpaper(uint64 paperId, uint64 accessHash)
+	FileOriginWallpaper(
+		uint64 paperId,
+		uint64 accessHash,
+		UserId ownerId,
+		const QString &slug)
 	: paperId(paperId)
-	, accessHash(accessHash) {
+	, accessHash(accessHash)
+	, ownerId(ownerId)
+	, slug(slug) {
 	}
 
 	uint64 paperId = 0;
 	uint64 accessHash = 0;
+	UserId ownerId = 0;
+	QString slug;
 
 	inline bool operator<(const FileOriginWallpaper &other) const {
 		return paperId < other.paperId;
diff --git a/Telegram/SourceFiles/data/data_wall_paper.cpp b/Telegram/SourceFiles/data/data_wall_paper.cpp
index e8437169c2..caa8fc5ec7 100644
--- a/Telegram/SourceFiles/data/data_wall_paper.cpp
+++ b/Telegram/SourceFiles/data/data_wall_paper.cpp
@@ -196,11 +196,17 @@ void WallPaper::loadDocument() const {
 }
 
 FileOrigin WallPaper::fileOrigin() const {
-	return FileOriginWallpaper(_id, _accessHash);
+	return FileOriginWallpaper(_id, _accessHash, _ownerId, _slug);
 }
 
-MTPInputWallPaper WallPaper::mtpInput() const {
-	return MTP_inputWallPaper(MTP_long(_id), MTP_long(_accessHash));
+UserId WallPaper::ownerId() const {
+	return _ownerId;
+}
+
+MTPInputWallPaper WallPaper::mtpInput(not_null<Main::Session*> session) const {
+	return (_ownerId && _ownerId != session->userId() && !_slug.isEmpty())
+		? MTP_inputWallPaperSlug(MTP_string(_slug))
+		: MTP_inputWallPaper(MTP_long(_id), MTP_long(_accessHash));
 }
 
 MTPWallPaperSettings WallPaper::mtpSettings() const {
@@ -324,6 +330,7 @@ std::optional<WallPaper> WallPaper::Create(
 	}
 	auto result = WallPaper(data.vid().v);
 	result._accessHash = data.vaccess_hash().v;
+	result._ownerId = session->userId();
 	result._flags = data.vflags().v;
 	result._slug = qs(data.vslug());
 	result._document = document;
@@ -372,7 +379,8 @@ QByteArray WallPaper::serialize() const {
 			<< _slug
 			<< qint32(_settings)
 			<< SerializeMaybeColor(_backgroundColor)
-			<< qint32(_intensity);
+			<< qint32(_intensity)
+			<< qint32(_ownerId);
 	}
 	return result;
 }
@@ -385,6 +393,7 @@ std::optional<WallPaper> WallPaper::FromSerialized(
 
 	auto id = quint64();
 	auto accessHash = quint64();
+	auto ownerId = qint32();
 	auto flags = qint32();
 	auto slug = QString();
 	auto settings = qint32();
@@ -401,6 +410,9 @@ std::optional<WallPaper> WallPaper::FromSerialized(
 		>> settings
 		>> backgroundColor
 		>> intensity;
+	if (!stream.atEnd()) {
+		stream >> ownerId;
+	}
 	if (stream.status() != QDataStream::Ok) {
 		return std::nullopt;
 	} else if (intensity < 0 || intensity > 100) {
@@ -408,6 +420,7 @@ std::optional<WallPaper> WallPaper::FromSerialized(
 	}
 	auto result = WallPaper(id);
 	result._accessHash = accessHash;
+	result._ownerId = ownerId;
 	result._flags = MTPDwallPaper::Flags::from_raw(flags);
 	result._slug = slug;
 	result._settings = MTPDwallPaperSettings::Flags::from_raw(settings);
diff --git a/Telegram/SourceFiles/data/data_wall_paper.h b/Telegram/SourceFiles/data/data_wall_paper.h
index 98957c78e7..72147d02b9 100644
--- a/Telegram/SourceFiles/data/data_wall_paper.h
+++ b/Telegram/SourceFiles/data/data_wall_paper.h
@@ -41,7 +41,9 @@ public:
 	void loadDocumentThumbnail() const;
 	[[nodiscard]] FileOrigin fileOrigin() const;
 
-	[[nodiscard]] MTPInputWallPaper mtpInput() const;
+	[[nodiscard]] UserId ownerId() const;
+	[[nodiscard]] MTPInputWallPaper mtpInput(
+		not_null<Main::Session*> session) const;
 	[[nodiscard]] MTPWallPaperSettings mtpSettings() const;
 
 	[[nodiscard]] WallPaper withUrlParams(
@@ -77,6 +79,7 @@ private:
 
 	WallPaperId _id = WallPaperId();
 	uint64 _accessHash = 0;
+	UserId _ownerId = 0;
 	MTPDwallPaper::Flags _flags;
 	QString _slug;
 
diff --git a/Telegram/SourceFiles/main/main_domain.cpp b/Telegram/SourceFiles/main/main_domain.cpp
index ce9457fdcd..12c923237e 100644
--- a/Telegram/SourceFiles/main/main_domain.cpp
+++ b/Telegram/SourceFiles/main/main_domain.cpp
@@ -38,9 +38,7 @@ Storage::StartResult Domain::start(const QByteArray &passcode) {
 	const auto result = _local->start(passcode);
 	if (result == Storage::StartResult::Success) {
 		activateAfterStarting();
-		if (Local::oldSettingsVersion() < AppVersion) {
-			Local::writeSettings();
-		}
+		Local::rewriteSettingsIfNeeded();
 	} else {
 		Assert(!started());
 	}
diff --git a/Telegram/SourceFiles/storage/details/storage_settings_scheme.cpp b/Telegram/SourceFiles/storage/details/storage_settings_scheme.cpp
index 72637b07e7..50ffccaabe 100644
--- a/Telegram/SourceFiles/storage/details/storage_settings_scheme.cpp
+++ b/Telegram/SourceFiles/storage/details/storage_settings_scheme.cpp
@@ -577,6 +577,16 @@ bool ReadSetting(
 		Window::Theme::SetNightModeValue(nightMode == 1);
 	} break;
 
+	case dbiBackgroundKey: {
+		quint64 keyDay = 0, keyNight = 0;
+		stream >> keyDay >> keyNight;
+		if (!CheckStreamStatus(stream)) return false;
+
+		context.backgroundKeyDay = keyDay;
+		context.backgroundKeyNight = keyNight;
+		context.backgroundKeysRead = true;
+	} break;
+
 	case dbiLangPackKey: {
 		quint64 langPackKey = 0;
 		stream >> langPackKey;
@@ -733,14 +743,15 @@ bool ReadSetting(
 		stream >> v;
 		if (!CheckStreamStatus(stream)) return false;
 
-		bool tile = (version < 8005 && !context.hasCustomDayBackground)
+		bool tile = (version < 8005 && !context.legacyHasCustomDayBackground)
 			? false
 			: (v == 1);
 		if (Window::Theme::IsNightMode()) {
-			context.tileNight = tile;
-		} else {
 			context.tileDay = tile;
+		} else {
+			context.tileNight = tile;
 		}
+		context.tileRead = true;
 	} break;
 
 	case dbiTileBackground: {
@@ -748,8 +759,9 @@ bool ReadSetting(
 		stream >> tileDay >> tileNight;
 		if (!CheckStreamStatus(stream)) return false;
 
-		context.tileDay = (tileDay == 1);
-		context.tileNight = (tileNight == 1);
+		context.tileDay = tileDay;
+		context.tileNight = tileNight;
+		context.tileRead = true;
 	} break;
 
 	case dbiAdaptiveForWideOld: {
diff --git a/Telegram/SourceFiles/storage/details/storage_settings_scheme.h b/Telegram/SourceFiles/storage/details/storage_settings_scheme.h
index 44e425543b..4a72b9e800 100644
--- a/Telegram/SourceFiles/storage/details/storage_settings_scheme.h
+++ b/Telegram/SourceFiles/storage/details/storage_settings_scheme.h
@@ -28,7 +28,7 @@ struct ReadSettingsContext {
 	}
 
 	// This field is read in ReadSetting.
-	bool hasCustomDayBackground = false;
+	bool legacyHasCustomDayBackground = false;
 
 	// Those fields are written in ReadSetting.
 	MTP::DcOptions fallbackConfigLegacyDcOptions
@@ -51,6 +51,12 @@ struct ReadSettingsContext {
 	FileKey themeKeyLegacy = 0;
 	FileKey themeKeyDay = 0;
 	FileKey themeKeyNight = 0;
+	FileKey backgroundKeyDay = 0;
+	FileKey backgroundKeyNight = 0;
+	bool backgroundKeysRead = false;
+	bool tileDay = false;
+	bool tileNight = true;
+	bool tileRead = false;
 	FileKey langPackKey = 0;
 	FileKey languagesKey = 0;
 
@@ -58,9 +64,6 @@ struct ReadSettingsContext {
 	std::vector<std::shared_ptr<MTP::AuthKey>> mtpLegacyKeys;
 	qint32 mtpLegacyMainDcId = 0;
 	qint32 mtpLegacyUserId = 0;
-
-	bool tileDay = false;
-	bool tileNight = true;
 };
 
 [[nodiscard]] bool ReadSetting(
@@ -159,6 +162,7 @@ enum {
 	dbiApplicationSettings = 0x5e,
 	dbiDialogsFiltersOld = 0x5f,
 	dbiFallbackProductionConfig = 0x60,
+	dbiBackgroundKey = 0x61,
 
 	dbiEncryptedWithSalt = 333,
 	dbiEncrypted = 444,
diff --git a/Telegram/SourceFiles/storage/localstorage.cpp b/Telegram/SourceFiles/storage/localstorage.cpp
index 97fd4279cf..6563361f47 100644
--- a/Telegram/SourceFiles/storage/localstorage.cpp
+++ b/Telegram/SourceFiles/storage/localstorage.cpp
@@ -43,6 +43,11 @@ namespace {
 constexpr auto kThemeFileSizeLimit = 5 * 1024 * 1024;
 constexpr auto kFileLoaderQueueStopTimeout = crl::time(5000);
 
+constexpr auto kSavedBackgroundFormat = QImage::Format_ARGB32_Premultiplied;
+constexpr auto kWallPaperLegacySerializeTagId = int32(-111);
+constexpr auto kWallPaperSerializeTagId = int32(-112);
+constexpr auto kWallPaperSidesLimit = 10'000;
+
 const auto kThemeNewPathRelativeTag = qstr("special://new_tag");
 
 using namespace Storage::details;
@@ -70,7 +75,14 @@ FileKey _themeKeyLegacy = 0;
 FileKey _langPackKey = 0;
 FileKey _languagesKey = 0;
 
+FileKey _backgroundKeyDay = 0;
+FileKey _backgroundKeyNight = 0;
+bool _useGlobalBackgroundKeys = false;
+bool _backgroundCanWrite = true;
+bool _backgroundMigrated = false;
+
 int32 _oldSettingsVersion = 0;
+bool _settingsRewritten;
 
 enum class WriteMapWhen {
 	Now,
@@ -120,8 +132,16 @@ void applyReadContext(ReadSettingsContext &&context) {
 	_themeKeyLegacy = context.themeKeyLegacy;
 	_themeKeyDay = context.themeKeyDay;
 	_themeKeyNight = context.themeKeyNight;
+	_backgroundKeyDay = context.backgroundKeyDay;
+	_backgroundKeyNight = context.backgroundKeyNight;
+	_useGlobalBackgroundKeys = context.backgroundKeysRead;
 	_langPackKey = context.langPackKey;
 	_languagesKey = context.languagesKey;
+
+	if (context.tileRead && _useGlobalBackgroundKeys) {
+		Window::Theme::Background()->setTileDayValue(context.tileDay);
+		Window::Theme::Background()->setTileNightValue(context.tileNight);
+	}
 }
 
 bool _readOldSettings(bool remove, ReadSettingsContext &context) {
@@ -436,6 +456,7 @@ void writeSettings() {
 
 	// Theme keys and night mode.
 	size += sizeof(quint32) + sizeof(quint64) * 2 + sizeof(quint32);
+	size += sizeof(quint32) + sizeof(quint64) * 2;
 	if (_langPackKey) {
 		size += sizeof(quint32) + sizeof(quint64);
 	}
@@ -471,6 +492,16 @@ void writeSettings() {
 		<< quint64(_themeKeyDay)
 		<< quint64(_themeKeyNight)
 		<< quint32(Window::Theme::IsNightMode() ? 1 : 0);
+	if (_useGlobalBackgroundKeys) {
+		data.stream
+			<< quint32(dbiBackgroundKey)
+			<< quint64(_backgroundKeyDay)
+			<< quint64(_backgroundKeyNight);
+		data.stream
+			<< quint32(dbiTileBackground)
+			<< qint32(Window::Theme::Background()->tileDay() ? 1 : 0)
+			<< qint32(Window::Theme::Background()->tileNight() ? 1 : 0);
+	}
 	if (_langPackKey) {
 		data.stream << quint32(dbiLangPackKey) << quint64(_langPackKey);
 	}
@@ -487,6 +518,15 @@ void writeSettings() {
 	settings.writeEncrypted(data, SettingsKey);
 }
 
+void rewriteSettingsIfNeeded() {
+	if (_settingsRewritten
+		|| (_oldSettingsVersion == AppVersion && !_backgroundMigrated)) {
+		return;
+	}
+	_settingsRewritten = true;
+	writeSettings();
+}
+
 const QString &AutoupdatePrefix(const QString &replaceWith = {}) {
 	Expects(!Core::UpdaterDisabled());
 
@@ -547,6 +587,207 @@ QString readAutoupdatePrefix() {
 	return result.replace(QRegularExpression("/+$"), QString());
 }
 
+void writeBackground(const Data::WallPaper &paper, const QImage &image) {
+	if (!_backgroundCanWrite) {
+		return;
+	}
+
+	_useGlobalBackgroundKeys = true;
+	auto &backgroundKey = Window::Theme::IsNightMode()
+		? _backgroundKeyNight
+		: _backgroundKeyDay;
+	auto imageData = QByteArray();
+	if (!image.isNull()) {
+		const auto width = qint32(image.width());
+		const auto height = qint32(image.height());
+		const auto perpixel = (image.depth() >> 3);
+		const auto srcperline = image.bytesPerLine();
+		const auto srcsize = srcperline * height;
+		const auto dstperline = width * perpixel;
+		const auto dstsize = dstperline * height;
+		const auto copy = (image.format() != kSavedBackgroundFormat)
+			? image.convertToFormat(kSavedBackgroundFormat)
+			: image;
+		imageData.resize(2 * sizeof(qint32) + dstsize);
+
+		auto dst = bytes::make_detached_span(imageData);
+		bytes::copy(dst, bytes::object_as_span(&width));
+		dst = dst.subspan(sizeof(qint32));
+		bytes::copy(dst, bytes::object_as_span(&height));
+		dst = dst.subspan(sizeof(qint32));
+		const auto src = bytes::make_span(image.constBits(), srcsize);
+		if (srcsize == dstsize) {
+			bytes::copy(dst, src);
+		} else {
+			for (auto y = 0; y != height; ++y) {
+				bytes::copy(dst, src.subspan(y * srcperline, dstperline));
+				dst = dst.subspan(dstperline);
+			}
+		}
+	}
+	if (!backgroundKey) {
+		backgroundKey = GenerateKey(_basePath);
+		writeSettings();
+	}
+	const auto serialized = paper.serialize();
+	quint32 size = sizeof(qint32)
+		+ Serialize::bytearraySize(serialized)
+		+ Serialize::bytearraySize(imageData);
+	EncryptedDescriptor data(size);
+	data.stream
+		<< qint32(kWallPaperSerializeTagId)
+		<< serialized
+		<< imageData;
+
+	FileWriteDescriptor file(backgroundKey, _basePath);
+	file.writeEncrypted(data, SettingsKey);
+}
+
+bool readBackground() {
+	FileReadDescriptor bg;
+	auto &backgroundKey = Window::Theme::IsNightMode()
+		? _backgroundKeyNight
+		: _backgroundKeyDay;
+	if (!ReadEncryptedFile(bg, backgroundKey, _basePath, SettingsKey)) {
+		if (backgroundKey) {
+			ClearKey(backgroundKey, _basePath);
+			backgroundKey = 0;
+			writeSettings();
+		}
+		return false;
+	}
+
+	qint32 legacyId = 0;
+	bg.stream >> legacyId;
+	const auto paper = [&] {
+		if (legacyId == kWallPaperLegacySerializeTagId) {
+			quint64 id = 0;
+			quint64 accessHash = 0;
+			quint32 flags = 0;
+			QString slug;
+			bg.stream
+				>> id
+				>> accessHash
+				>> flags
+				>> slug;
+			return Data::WallPaper::FromLegacySerialized(
+				id,
+				accessHash,
+				flags,
+				slug);
+		} else if (legacyId == kWallPaperSerializeTagId) {
+			QByteArray serialized;
+			bg.stream >> serialized;
+			return Data::WallPaper::FromSerialized(serialized);
+		} else {
+			return Data::WallPaper::FromLegacyId(legacyId);
+		}
+	}();
+	if (bg.stream.status() != QDataStream::Ok || !paper) {
+		return false;
+	}
+
+	QByteArray imageData;
+	bg.stream >> imageData;
+	const auto isOldEmptyImage = (bg.stream.status() != QDataStream::Ok);
+	if (isOldEmptyImage
+		|| Data::IsLegacy1DefaultWallPaper(*paper)
+		|| Data::IsDefaultWallPaper(*paper)) {
+		_backgroundCanWrite = false;
+		if (isOldEmptyImage || bg.version < 8005) {
+			Window::Theme::Background()->set(Data::DefaultWallPaper());
+			Window::Theme::Background()->setTile(false);
+		} else {
+			Window::Theme::Background()->set(*paper);
+		}
+		_backgroundCanWrite = true;
+		return true;
+	} else if (Data::IsThemeWallPaper(*paper) && imageData.isEmpty()) {
+		_backgroundCanWrite = false;
+		Window::Theme::Background()->set(*paper);
+		_backgroundCanWrite = true;
+		return true;
+	}
+	auto image = QImage();
+	if (legacyId == kWallPaperSerializeTagId) {
+		const auto perpixel = 4;
+		auto src = bytes::make_span(imageData);
+		auto width = qint32();
+		auto height = qint32();
+		if (src.size() > 2 * sizeof(qint32)) {
+			bytes::copy(
+				bytes::object_as_span(&width),
+				src.subspan(0, sizeof(qint32)));
+			src = src.subspan(sizeof(qint32));
+			bytes::copy(
+				bytes::object_as_span(&height),
+				src.subspan(0, sizeof(qint32)));
+			src = src.subspan(sizeof(qint32));
+			if (width + height <= kWallPaperSidesLimit
+				&& src.size() == width * height * perpixel) {
+				image = QImage(
+					width,
+					height,
+					QImage::Format_ARGB32_Premultiplied);
+				if (!image.isNull()) {
+					const auto srcperline = width * perpixel;
+					const auto srcsize = srcperline * height;
+					const auto dstperline = image.bytesPerLine();
+					const auto dstsize = dstperline * height;
+					Assert(srcsize == dstsize);
+					bytes::copy(
+						bytes::make_span(image.bits(), dstsize),
+						src);
+				}
+			}
+		}
+	} else {
+		auto buffer = QBuffer(&imageData);
+		auto reader = QImageReader(&buffer);
+#ifndef OS_MAC_OLD
+		reader.setAutoTransform(true);
+#endif // OS_MAC_OLD
+		if (!reader.read(&image)) {
+			image = QImage();
+		}
+	}
+	if (!image.isNull() || paper->backgroundColor()) {
+		_backgroundCanWrite = false;
+		Window::Theme::Background()->set(*paper, std::move(image));
+		_backgroundCanWrite = true;
+		return true;
+	}
+	return false;
+}
+
+void moveLegacyBackground(
+		const QString &fromBasePath,
+		const MTP::AuthKeyPtr &fromLocalKey,
+		uint64 legacyBackgroundKeyDay,
+		uint64 legacyBackgroundKeyNight) {
+	if (_useGlobalBackgroundKeys
+		|| (!legacyBackgroundKeyDay && !legacyBackgroundKeyNight)) {
+		return;
+	}
+	const auto move = [&](uint64 from, FileKey &to) {
+		if (!from || to) {
+			return;
+		}
+		to = GenerateKey(_basePath);
+		FileReadDescriptor read;
+		if (!ReadEncryptedFile(read, from, fromBasePath, fromLocalKey)) {
+			return;
+		}
+		EncryptedDescriptor data;
+		data.data = read.data;
+		FileWriteDescriptor write(to, _basePath);
+		write.writeEncrypted(data, SettingsKey);
+	};
+	move(legacyBackgroundKeyDay, _backgroundKeyDay);
+	move(legacyBackgroundKeyNight, _backgroundKeyNight);
+	_backgroundMigrated = true;
+}
+
 void reset() {
 	if (_localLoader) {
 		_localLoader->stop();
diff --git a/Telegram/SourceFiles/storage/localstorage.h b/Telegram/SourceFiles/storage/localstorage.h
index 50890a034f..576a718dbb 100644
--- a/Telegram/SourceFiles/storage/localstorage.h
+++ b/Telegram/SourceFiles/storage/localstorage.h
@@ -41,16 +41,30 @@ namespace Export {
 struct Settings;
 } // namespace Export
 
+namespace MTP {
+class AuthKey;
+using AuthKeyPtr = std::shared_ptr<AuthKey>;
+} // namespace MTP
+
 namespace Local {
 
 void start();
 void finish();
 
 void writeSettings();
+void rewriteSettingsIfNeeded();
 
 void writeAutoupdatePrefix(const QString &prefix);
 QString readAutoupdatePrefix();
 
+void writeBackground(const Data::WallPaper &paper, const QImage &image);
+bool readBackground();
+void moveLegacyBackground(
+	const QString &fromBasePath,
+	const MTP::AuthKeyPtr &fromLocalKey,
+	uint64 legacyBackgroundKeyDay,
+	uint64 legacyBackgroundKeyNight);
+
 void reset();
 
 enum ClearManagerTask {
diff --git a/Telegram/SourceFiles/storage/storage_account.cpp b/Telegram/SourceFiles/storage/storage_account.cpp
index 904b455ed9..e6cc277828 100644
--- a/Telegram/SourceFiles/storage/storage_account.cpp
+++ b/Telegram/SourceFiles/storage/storage_account.cpp
@@ -39,17 +39,12 @@ using namespace details;
 using Database = Cache::Database;
 
 constexpr auto kDelayedWriteTimeout = crl::time(1000);
-constexpr auto kSavedBackgroundFormat = QImage::Format_ARGB32_Premultiplied;
 
 constexpr auto kStickersVersionTag = quint32(-1);
 constexpr auto kStickersSerializeVersion = 1;
 constexpr auto kMaxSavedStickerSetsCount = 1000;
 constexpr auto kDefaultStickerInstallDate = TimeId(1);
 
-constexpr auto kWallPaperLegacySerializeTagId = int32(-111);
-constexpr auto kWallPaperSerializeTagId = int32(-112);
-constexpr auto kWallPaperSidesLimit = 10'000;
-
 constexpr auto kSinglePeerTypeUser = qint32(1);
 constexpr auto kSinglePeerTypeChat = qint32(2);
 constexpr auto kSinglePeerTypeChannel = qint32(3);
@@ -65,7 +60,7 @@ enum { // Local Storage Keys
 	lskLegacyStickerImages = 0x05, // legacy
 	lskLegacyAudios = 0x06, // legacy
 	lskRecentStickersOld = 0x07, // no data
-	lskBackgroundOld = 0x08, // no data
+	lskBackgroundOldOld = 0x08, // no data
 	lskUserSettings = 0x09, // no data
 	lskRecentHashtagsAndBots = 0x0a, // no data
 	lskStickersOld = 0x0b, // no data
@@ -77,7 +72,7 @@ enum { // Local Storage Keys
 	lskTrustedBots = 0x11, // no data
 	lskFavedStickers = 0x12, // no data
 	lskExportSettings = 0x13, // no data
-	lskBackground = 0x14, // no data
+	lskBackgroundOld = 0x14, // no data
 	lskSelfSerialized = 0x15, // serialized self
 };
 
@@ -173,8 +168,8 @@ base::flat_set<QString> Account::collectGoodNames() const {
 		_archivedStickersKey,
 		_recentStickersKeyOld,
 		_savedGifsKey,
-		_backgroundKeyNight,
-		_backgroundKeyDay,
+		_legacyBackgroundKeyNight,
+		_legacyBackgroundKeyDay,
 		_recentHashtagsAndBotsKey,
 		_exportSettingsKey,
 		_trustedBotsKey,
@@ -259,7 +254,7 @@ Account::ReadMapResult Account::readMapWith(
 	quint64 recentStickersKeyOld = 0;
 	quint64 installedStickersKey = 0, featuredStickersKey = 0, recentStickersKey = 0, favedStickersKey = 0, archivedStickersKey = 0;
 	quint64 savedGifsKey = 0;
-	quint64 backgroundKeyDay = 0, backgroundKeyNight = 0;
+	quint64 legacyBackgroundKeyDay = 0, legacyBackgroundKeyNight = 0;
 	quint64 userSettingsKey = 0, recentHashtagsAndBotsKey = 0, exportSettingsKey = 0;
 	while (!map.stream.atEnd()) {
 		quint32 keyType;
@@ -315,13 +310,13 @@ Account::ReadMapResult Account::readMapWith(
 		case lskRecentStickersOld: {
 			map.stream >> recentStickersKeyOld;
 		} break;
-		case lskBackgroundOld: {
+		case lskBackgroundOldOld: {
 			map.stream >> (Window::Theme::IsNightMode()
-				? backgroundKeyNight
-				: backgroundKeyDay);
+				? legacyBackgroundKeyNight
+				: legacyBackgroundKeyDay);
 		} break;
-		case lskBackground: {
-			map.stream >> backgroundKeyDay >> backgroundKeyNight;
+		case lskBackgroundOld: {
+			map.stream >> legacyBackgroundKeyDay >> legacyBackgroundKeyNight;
 		} break;
 		case lskUserSettings: {
 			map.stream >> userSettingsKey;
@@ -376,8 +371,8 @@ Account::ReadMapResult Account::readMapWith(
 	_favedStickersKey = favedStickersKey;
 	_archivedStickersKey = archivedStickersKey;
 	_savedGifsKey = savedGifsKey;
-	_backgroundKeyDay = backgroundKeyDay;
-	_backgroundKeyNight = backgroundKeyNight;
+	_legacyBackgroundKeyDay = legacyBackgroundKeyDay;
+	_legacyBackgroundKeyNight = legacyBackgroundKeyNight;
 	_settingsKey = userSettingsKey;
 	_recentHashtagsAndBotsKey = recentHashtagsAndBotsKey;
 	_exportSettingsKey = exportSettingsKey;
@@ -392,6 +387,13 @@ Account::ReadMapResult Account::readMapWith(
 	if (_locationsKey) {
 		readLocations();
 	}
+	if (_legacyBackgroundKeyDay || _legacyBackgroundKeyNight) {
+		Local::moveLegacyBackground(
+			_basePath,
+			_localKey,
+			_legacyBackgroundKeyDay,
+			_legacyBackgroundKeyNight);
+	}
 
 	auto stored = readSessionSettings();
 	readMtpData();
@@ -403,6 +405,7 @@ Account::ReadMapResult Account::readMapWith(
 		_oldMapVersion);
 
 	LOG(("Map read time: %1").arg(crl::now() - ms));
+
 	return ReadMapResult::Success;
 }
 
@@ -469,7 +472,6 @@ void Account::writeMap() {
 	}
 	if (_favedStickersKey) mapSize += sizeof(quint32) + sizeof(quint64);
 	if (_savedGifsKey) mapSize += sizeof(quint32) + sizeof(quint64);
-	if (_backgroundKeyDay || _backgroundKeyNight) mapSize += sizeof(quint32) + sizeof(quint64) + sizeof(quint64);
 	if (_settingsKey) mapSize += sizeof(quint32) + sizeof(quint64);
 	if (_recentHashtagsAndBotsKey) mapSize += sizeof(quint32) + sizeof(quint64);
 	if (_exportSettingsKey) mapSize += sizeof(quint32) + sizeof(quint64);
@@ -509,12 +511,6 @@ void Account::writeMap() {
 	if (_savedGifsKey) {
 		mapData.stream << quint32(lskSavedGifs) << quint64(_savedGifsKey);
 	}
-	if (_backgroundKeyDay || _backgroundKeyNight) {
-		mapData.stream
-			<< quint32(lskBackground)
-			<< quint64(_backgroundKeyDay)
-			<< quint64(_backgroundKeyNight);
-	}
 	if (_settingsKey) {
 		mapData.stream << quint32(lskUserSettings) << quint64(_settingsKey);
 	}
@@ -542,7 +538,7 @@ void Account::reset() {
 	_favedStickersKey = 0;
 	_archivedStickersKey = 0;
 	_savedGifsKey = 0;
-	_backgroundKeyDay = _backgroundKeyNight = 0;
+	_legacyBackgroundKeyDay = _legacyBackgroundKeyNight = 0;
 	_settingsKey = _recentHashtagsAndBotsKey = _exportSettingsKey = 0;
 	_oldMapVersion = 0;
 	_fileLocations.clear();
@@ -764,10 +760,6 @@ void Account::writeSessionSettings(Main::SessionSettings *stored) {
 	}
 
 	EncryptedDescriptor data(size);
-	data.stream
-		<< quint32(dbiTileBackground)
-		<< qint32(Window::Theme::Background()->tileDay() ? 1 : 0)
-		<< qint32(Window::Theme::Background()->tileNight() ? 1 : 0);
 	data.stream << quint32(dbiUseExternalVideoPlayer) << qint32(cUseExternalVideoPlayer());
 	data.stream << quint32(dbiCacheSettings) << qint64(_cacheTotalSizeLimit) << qint32(_cacheTotalTimeLimit) << qint64(_cacheBigFileTotalSizeLimit) << qint32(_cacheBigFileTotalTimeLimit);
 	if (!userData.isEmpty()) {
@@ -783,7 +775,7 @@ void Account::writeSessionSettings(Main::SessionSettings *stored) {
 
 ReadSettingsContext Account::prepareReadSettingsContext() const {
 	return ReadSettingsContext{
-		.hasCustomDayBackground = (_backgroundKeyDay != 0)
+		.legacyHasCustomDayBackground = (_legacyBackgroundKeyDay != 0)
 	};
 }
 
@@ -845,9 +837,10 @@ std::unique_ptr<Main::SessionSettings> Account::applyReadContext(
 		}
 	}
 
-	// #TODO multi
-	//Window::Theme::Background()->setTileDayValue(context.tileDay);
-	//Window::Theme::Background()->setTileNightValue(context.tileNight);
+	if (context.tileRead) {
+		Window::Theme::Background()->setTileDayValue(context.tileDay);
+		Window::Theme::Background()->setTileNightValue(context.tileNight);
+	}
 
 	return std::move(context.sessionSettingsStorage);
 }
@@ -1955,185 +1948,6 @@ void Account::readSavedGifs() {
 	}
 }
 
-void Account::writeBackground(
-		const Data::WallPaper &paper,
-		const QImage &image) {
-	if (!_backgroundCanWrite) {
-		return;
-	}
-
-	if (!_localKey) {
-		LOG(("App Error: localkey not created in writeBackground()"));
-		return;
-	}
-
-	auto &backgroundKey = Window::Theme::IsNightMode()
-		? _backgroundKeyNight
-		: _backgroundKeyDay;
-	auto imageData = QByteArray();
-	if (!image.isNull()) {
-		const auto width = qint32(image.width());
-		const auto height = qint32(image.height());
-		const auto perpixel = (image.depth() >> 3);
-		const auto srcperline = image.bytesPerLine();
-		const auto srcsize = srcperline * height;
-		const auto dstperline = width * perpixel;
-		const auto dstsize = dstperline * height;
-		const auto copy = (image.format() != kSavedBackgroundFormat)
-			? image.convertToFormat(kSavedBackgroundFormat)
-			: image;
-		imageData.resize(2 * sizeof(qint32) + dstsize);
-
-		auto dst = bytes::make_detached_span(imageData);
-		bytes::copy(dst, bytes::object_as_span(&width));
-		dst = dst.subspan(sizeof(qint32));
-		bytes::copy(dst, bytes::object_as_span(&height));
-		dst = dst.subspan(sizeof(qint32));
-		const auto src = bytes::make_span(image.constBits(), srcsize);
-		if (srcsize == dstsize) {
-			bytes::copy(dst, src);
-		} else {
-			for (auto y = 0; y != height; ++y) {
-				bytes::copy(dst, src.subspan(y * srcperline, dstperline));
-				dst = dst.subspan(dstperline);
-			}
-		}
-	}
-	if (!backgroundKey) {
-		backgroundKey = GenerateKey(_basePath);
-		writeMapQueued();
-	}
-	const auto serialized = paper.serialize();
-	quint32 size = sizeof(qint32)
-		+ Serialize::bytearraySize(serialized)
-		+ Serialize::bytearraySize(imageData);
-	EncryptedDescriptor data(size);
-	data.stream
-		<< qint32(kWallPaperSerializeTagId)
-		<< serialized
-		<< imageData;
-
-	FileWriteDescriptor file(backgroundKey, _basePath);
-	file.writeEncrypted(data, _localKey);
-}
-
-bool Account::readBackground() {
-	FileReadDescriptor bg;
-	auto &backgroundKey = Window::Theme::IsNightMode()
-		? _backgroundKeyNight
-		: _backgroundKeyDay;
-	if (!ReadEncryptedFile(bg, backgroundKey, _basePath, _localKey)) {
-		if (backgroundKey) {
-			ClearKey(backgroundKey, _basePath);
-			backgroundKey = 0;
-			writeMapDelayed();
-		}
-		return false;
-	}
-
-	qint32 legacyId = 0;
-	bg.stream >> legacyId;
-	const auto paper = [&] {
-		if (legacyId == kWallPaperLegacySerializeTagId) {
-			quint64 id = 0;
-			quint64 accessHash = 0;
-			quint32 flags = 0;
-			QString slug;
-			bg.stream
-				>> id
-				>> accessHash
-				>> flags
-				>> slug;
-			return Data::WallPaper::FromLegacySerialized(
-				id,
-				accessHash,
-				flags,
-				slug);
-		} else if (legacyId == kWallPaperSerializeTagId) {
-			QByteArray serialized;
-			bg.stream >> serialized;
-			return Data::WallPaper::FromSerialized(serialized);
-		} else {
-			return Data::WallPaper::FromLegacyId(legacyId);
-		}
-	}();
-	if (bg.stream.status() != QDataStream::Ok || !paper) {
-		return false;
-	}
-
-	QByteArray imageData;
-	bg.stream >> imageData;
-	const auto isOldEmptyImage = (bg.stream.status() != QDataStream::Ok);
-	if (isOldEmptyImage
-		|| Data::IsLegacy1DefaultWallPaper(*paper)
-		|| Data::IsDefaultWallPaper(*paper)) {
-		_backgroundCanWrite = false;
-		if (isOldEmptyImage || bg.version < 8005) {
-			Window::Theme::Background()->set(Data::DefaultWallPaper());
-			Window::Theme::Background()->setTile(false);
-		} else {
-			Window::Theme::Background()->set(*paper);
-		}
-		_backgroundCanWrite = true;
-		return true;
-	} else if (Data::IsThemeWallPaper(*paper) && imageData.isEmpty()) {
-		_backgroundCanWrite = false;
-		Window::Theme::Background()->set(*paper);
-		_backgroundCanWrite = true;
-		return true;
-	}
-	auto image = QImage();
-	if (legacyId == kWallPaperSerializeTagId) {
-		const auto perpixel = 4;
-		auto src = bytes::make_span(imageData);
-		auto width = qint32();
-		auto height = qint32();
-		if (src.size() > 2 * sizeof(qint32)) {
-			bytes::copy(
-				bytes::object_as_span(&width),
-				src.subspan(0, sizeof(qint32)));
-			src = src.subspan(sizeof(qint32));
-			bytes::copy(
-				bytes::object_as_span(&height),
-				src.subspan(0, sizeof(qint32)));
-			src = src.subspan(sizeof(qint32));
-			if (width + height <= kWallPaperSidesLimit
-				&& src.size() == width * height * perpixel) {
-				image = QImage(
-					width,
-					height,
-					QImage::Format_ARGB32_Premultiplied);
-				if (!image.isNull()) {
-					const auto srcperline = width * perpixel;
-					const auto srcsize = srcperline * height;
-					const auto dstperline = image.bytesPerLine();
-					const auto dstsize = dstperline * height;
-					Assert(srcsize == dstsize);
-					bytes::copy(
-						bytes::make_span(image.bits(), dstsize),
-						src);
-				}
-			}
-		}
-	} else {
-		auto buffer = QBuffer(&imageData);
-		auto reader = QImageReader(&buffer);
-#ifndef OS_MAC_OLD
-		reader.setAutoTransform(true);
-#endif // OS_MAC_OLD
-		if (!reader.read(&image)) {
-			image = QImage();
-		}
-	}
-	if (!image.isNull() || paper->backgroundColor()) {
-		_backgroundCanWrite = false;
-		Window::Theme::Background()->set(*paper, std::move(image));
-		_backgroundCanWrite = true;
-		return true;
-	}
-	return false;
-}
-
 void Account::writeRecentHashtagsAndBots() {
 	const auto &write = cRecentWriteHashtags();
 	const auto &search = cRecentSearchHashtags();
diff --git a/Telegram/SourceFiles/storage/storage_account.h b/Telegram/SourceFiles/storage/storage_account.h
index eb922fb64e..6c65fd4081 100644
--- a/Telegram/SourceFiles/storage/storage_account.h
+++ b/Telegram/SourceFiles/storage/storage_account.h
@@ -71,9 +71,6 @@ public:
 	void writeMtpData();
 	void writeMtpConfig();
 
-	void writeBackground(const Data::WallPaper &paper, const QImage &image);
-	bool readBackground();
-
 	void writeDrafts(not_null<History*> history);
 	void writeDrafts(
 		const PeerId &peer,
@@ -232,8 +229,8 @@ private:
 	FileKey _archivedStickersKey = 0;
 	FileKey _savedGifsKey = 0;
 	FileKey _recentStickersKeyOld = 0;
-	FileKey _backgroundKeyDay = 0;
-	FileKey _backgroundKeyNight = 0;
+	FileKey _legacyBackgroundKeyDay = 0;
+	FileKey _legacyBackgroundKeyNight = 0;
 	FileKey _settingsKey = 0;
 	FileKey _recentHashtagsAndBotsKey = 0;
 	FileKey _exportSettingsKey = 0;
@@ -245,7 +242,6 @@ private:
 
 	base::flat_set<uint64> _trustedBots;
 	bool _trustedBotsRead = false;
-	bool _backgroundCanWrite = true;
 	bool _readingUserSettings = false;
 	bool _recentHashtagsAndBotsWereRead = false;
 
diff --git a/Telegram/SourceFiles/window/themes/window_theme.cpp b/Telegram/SourceFiles/window/themes/window_theme.cpp
index f5f8bbc8de..2f170c3b46 100644
--- a/Telegram/SourceFiles/window/themes/window_theme.cpp
+++ b/Telegram/SourceFiles/window/themes/window_theme.cpp
@@ -14,7 +14,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "main/main_session.h"
 #include "apiwrap.h"
 #include "storage/localstorage.h"
-#include "storage/storage_account.h"
 #include "storage/localimageloader.h"
 #include "storage/file_upload.h"
 #include "base/parse_helper.h"
@@ -531,10 +530,6 @@ ChatBackground::ChatBackground() : _adjustableColors({
 	});
 }
 
-Storage::Account &ChatBackground::local() const {
-	return Core::App().activeAccount().local();
-}
-
 void ChatBackground::setThemeData(QImage &&themeImage, bool themeTile) {
 	_themeImage = validateBackgroundImage(std::move(themeImage));
 	_themeTile = themeTile;
@@ -544,7 +539,7 @@ void ChatBackground::start() {
 	if (!Data::details::IsUninitializedWallPaper(_paper)) {
 		return;
 	}
-	if (!local().readBackground()) {
+	if (!Local::readBackground()) {
 		set(Data::ThemeWallPaper());
 	}
 
@@ -659,7 +654,7 @@ void ChatBackground::set(const Data::WallPaper &paper, QImage image) {
 			setPaper(Data::DefaultWallPaper().withParamsFrom(_paper));
 			image.load(qsl(":/gui/art/bg.jpg"));
 		}
-		local().writeBackground(
+		Local::writeBackground(
 			_paper,
 			((Data::IsDefaultWallPaper(_paper)
 				|| Data::IsLegacy1DefaultWallPaper(_paper))
@@ -875,7 +870,7 @@ void ChatBackground::setTile(bool tile) {
 	if (this->tile() != old) {
 		if (!Data::details::IsTestingThemeWallPaper(_paper)
 			&& !Data::details::IsTestingDefaultWallPaper(_paper)) {
-			local().writeSessionSettings();
+			Local::writeSettings();
 		}
 		notify(BackgroundUpdate(BackgroundUpdate::Type::Changed, tile));
 	}
@@ -1030,9 +1025,9 @@ bool ChatBackground::isNonDefaultBackground() {
 
 void ChatBackground::writeNewBackgroundSettings() {
 	if (tile() != _tileForRevert) {
-		local().writeSessionSettings();
+		Local::writeSettings();
 	}
-	local().writeBackground(
+	Local::writeBackground(
 		_paper,
 		((Data::IsThemeWallPaper(_paper)
 			|| Data::IsDefaultWallPaper(_paper))
@@ -1116,13 +1111,10 @@ void ChatBackground::reapplyWithNightMode(
 			}
 			ClearApplying();
 			keepApplied(saved.object, settingExactTheme);
-			if (tile() != _tileForRevert) {
-				local().writeSessionSettings();
-			}
-			if (nightModeChanged) {
+			if (tile() != _tileForRevert || nightModeChanged) {
 				Local::writeSettings();
 			}
-			if (!settingExactTheme && !local().readBackground()) {
+			if (!settingExactTheme && !Local::readBackground()) {
 				set(Data::ThemeWallPaper());
 			}
 		};
diff --git a/Telegram/SourceFiles/window/themes/window_theme.h b/Telegram/SourceFiles/window/themes/window_theme.h
index 109111573c..be9833fb9a 100644
--- a/Telegram/SourceFiles/window/themes/window_theme.h
+++ b/Telegram/SourceFiles/window/themes/window_theme.h
@@ -14,10 +14,6 @@ namespace Main {
 class Session;
 } // namespace Main
 
-namespace Storage {
-class Account;
-} // namespace Storage
-
 namespace Window {
 namespace Theme {
 
@@ -181,8 +177,6 @@ private:
 		QColor original;
 	};
 
-	Storage::Account &local() const;
-
 	void ensureStarted();
 	void saveForRevert();
 	void setPreparedImage(QImage original, QImage prepared);