diff --git a/td/telegram/Photo.cpp b/td/telegram/Photo.cpp
index 3131b4f0..f6fd675e 100644
--- a/td/telegram/Photo.cpp
+++ b/td/telegram/Photo.cpp
@@ -54,11 +54,29 @@ tl_object_ptr<telegram_api::InputPeer> PhotoSizeSource::DialogPhoto::get_input_p
   }
 }
 
+FileType get_photo_size_source_file_type(const PhotoSizeSource &source) {
+  switch (source.type) {
+    case PhotoSizeSource::Type::Thumbnail:
+      return source.thumbnail().file_type;
+    case PhotoSizeSource::Type::DialogPhoto:
+      return FileType::ProfilePhoto;
+    case PhotoSizeSource::Type::StickerSetThumbnail:
+      return FileType::Thumbnail;
+    case PhotoSizeSource::Type::Empty:
+    default:
+      UNREACHABLE();
+      return FileType::Thumbnail;
+  }
+}
+
 bool operator==(const PhotoSizeSource &lhs, const PhotoSizeSource &rhs) {
-  if (lhs.type != rhs.type || lhs.file_type != rhs.file_type) {
+  if (lhs.type != rhs.type) {
     return false;
   }
   switch (lhs.type) {
+    case PhotoSizeSource::Type::Thumbnail:
+      return lhs.thumbnail().file_type == rhs.thumbnail().file_type &&
+             lhs.thumbnail().thumbnail_type == rhs.thumbnail().thumbnail_type;
     case PhotoSizeSource::Type::DialogPhoto:
       return lhs.dialog_photo().dialog_id == rhs.dialog_photo().dialog_id &&
              lhs.dialog_photo().dialog_access_hash == rhs.dialog_photo().dialog_access_hash &&
@@ -66,8 +84,6 @@ bool operator==(const PhotoSizeSource &lhs, const PhotoSizeSource &rhs) {
     case PhotoSizeSource::Type::StickerSetThumbnail:
       return lhs.sticker_set_thumbnail().sticker_set_id == rhs.sticker_set_thumbnail().sticker_set_id &&
              lhs.sticker_set_thumbnail().sticker_set_access_hash == rhs.sticker_set_thumbnail().sticker_set_access_hash;
-    case PhotoSizeSource::Type::Thumbnail:
-      return lhs.thumbnail().thumbnail_type == rhs.thumbnail().thumbnail_type;
     case PhotoSizeSource::Type::Empty:
     default:
       return true;
@@ -153,9 +169,9 @@ static FileId register_photo(FileManager *file_manager, const PhotoSizeSource &s
                              bool is_png = false) {
   int32 local_id = location->local_id_;
   int64 volume_id = location->volume_id_;
-  LOG(DEBUG) << "Receive " << (is_webp ? "webp" : (is_png ? "png" : "jpeg")) << " photo of type " << source.file_type
-             << " in [" << dc_id << "," << volume_id << "," << local_id << "]. Id: (" << id << ", " << access_hash
-             << ")";
+  LOG(DEBUG) << "Receive " << (is_webp ? "webp" : (is_png ? "png" : "jpeg")) << " photo of type "
+             << get_photo_size_source_file_type(source) << " in [" << dc_id << "," << volume_id << "," << local_id
+             << "]. Id: (" << id << ", " << access_hash << ")";
   auto suggested_name = PSTRING() << static_cast<uint64>(volume_id) << "_" << static_cast<uint64>(local_id)
                                   << (is_webp ? ".webp" : (is_png ? ".png" : ".jpg"));
   auto file_location_source = owner_dialog_id.get_type() == DialogType::SecretChat ? FileLocationSource::FromUser
diff --git a/td/telegram/Photo.h b/td/telegram/Photo.h
index 27d1704d..4958cd7c 100644
--- a/td/telegram/Photo.h
+++ b/td/telegram/Photo.h
@@ -50,14 +50,20 @@ struct PhotoSize {
 struct PhotoSizeSource {
   enum class Type : int32 { Empty, Thumbnail, DialogPhoto, StickerSetThumbnail };
   Type type;
-  FileType file_type;
 
   // for photos, document thumbnails, encrypted thumbnails
   struct Thumbnail {
     Thumbnail() = default;
-    explicit Thumbnail(int32 thumbnail_type) : thumbnail_type(thumbnail_type) {
+    Thumbnail(FileType file_type, int32 thumbnail_type) : thumbnail_type(thumbnail_type) {
     }
+
+    FileType file_type;
     int32 thumbnail_type = 0;
+
+    template <class StorerT>
+    void store(StorerT &storer) const;
+    template <class ParserT>
+    void parse(ParserT &parser);
   };
 
   // for dialog photos
@@ -100,20 +106,16 @@ struct PhotoSizeSource {
   };
   Variant<Thumbnail, DialogPhoto, StickerSetThumbnail> variant;
 
-  PhotoSizeSource() : type(Type::Empty), file_type(FileType::None) {
+  PhotoSizeSource() : type(Type::Empty) {
   }
   PhotoSizeSource(FileType file_type, int32 thumbnail_type)
-      : type(Type::Thumbnail), file_type(file_type), variant(Thumbnail(thumbnail_type)) {
+      : type(Type::Thumbnail), variant(Thumbnail(file_type, thumbnail_type)) {
   }
   PhotoSizeSource(DialogId dialog_id, int64 dialog_access_hash, bool is_big)
-      : type(Type::DialogPhoto)
-      , file_type(FileType::ProfilePhoto)
-      , variant(DialogPhoto(dialog_id, dialog_access_hash, is_big)) {
+      : type(Type::DialogPhoto), variant(DialogPhoto(dialog_id, dialog_access_hash, is_big)) {
   }
   PhotoSizeSource(int64 sticker_set_id, int64 sticker_set_access_hash)
-      : type(Type::StickerSetThumbnail)
-      , file_type(FileType::Thumbnail)
-      , variant(StickerSetThumbnail(sticker_set_id, sticker_set_access_hash)) {
+      : type(Type::StickerSetThumbnail), variant(StickerSetThumbnail(sticker_set_id, sticker_set_access_hash)) {
   }
 
   Thumbnail &thumbnail() {
@@ -135,9 +137,6 @@ struct PhotoSizeSource {
   void parse(ParserT &parser);
 };
 
-bool operator==(const PhotoSizeSource &lhs, const PhotoSizeSource &rhs);
-bool operator!=(const PhotoSizeSource &lhs, const PhotoSizeSource &rhs);
-
 struct Photo {
   int64 id = 0;
   int32 date = 0;
@@ -148,6 +147,11 @@ struct Photo {
   vector<FileId> sticker_file_ids;
 };
 
+FileType get_photo_size_source_file_type(const PhotoSizeSource &source);
+
+bool operator==(const PhotoSizeSource &lhs, const PhotoSizeSource &rhs);
+bool operator!=(const PhotoSizeSource &lhs, const PhotoSizeSource &rhs);
+
 Dimensions get_dimensions(int32 width, int32 height);
 
 bool operator==(const Dimensions &lhs, const Dimensions &rhs);
diff --git a/td/telegram/Photo.hpp b/td/telegram/Photo.hpp
index 98d288ec..ef32ce68 100644
--- a/td/telegram/Photo.hpp
+++ b/td/telegram/Photo.hpp
@@ -13,10 +13,25 @@
 #include "td/utils/logging.h"
 #include "td/utils/tl_helpers.h"
 
-#include <limits>
-
 namespace td {
 
+template <class StorerT>
+void PhotoSizeSource::Thumbnail::store(StorerT &storer) const {
+  using td::store;
+  store(file_type, storer);
+  store(thumbnail_type, storer);
+}
+
+template <class ParserT>
+void PhotoSizeSource::Thumbnail::parse(ParserT &parser) {
+  using td::parse;
+  parse(file_type, parser);
+  parse(thumbnail_type, parser);
+  if (thumbnail_type < 0 || thumbnail_type > 255) {
+    parser.set_error("Wrong thumbnail type");
+  }
+}
+
 template <class StorerT>
 void PhotoSizeSource::StickerSetThumbnail::store(StorerT &storer) const {
   using td::store;
@@ -59,20 +74,17 @@ void PhotoSizeSource::DialogPhoto::parse(ParserT &parser) {
 template <class StorerT>
 void PhotoSizeSource::store(StorerT &storer) const {
   using td::store;
-  store(file_type, storer);
   store(type, storer);
   switch (type) {
+    case Type::Thumbnail:
+      store(thumbnail(), storer);
+      break;
     case Type::DialogPhoto:
       store(dialog_photo(), storer);
       break;
     case Type::StickerSetThumbnail:
       store(sticker_set_thumbnail(), storer);
       break;
-    case Type::Thumbnail: {
-      auto &thumbnail = this->thumbnail();
-      store(thumbnail.thumbnail_type, storer);
-      break;
-    }
     case Type::Empty:
       break;
   }
@@ -81,9 +93,14 @@ void PhotoSizeSource::store(StorerT &storer) const {
 template <class ParserT>
 void PhotoSizeSource::parse(ParserT &parser) {
   using td::parse;
-  parse(file_type, parser);
   parse(type, parser);
   switch (type) {
+    case Type::Thumbnail: {
+      Thumbnail thumbnail;
+      parse(thumbnail, parser);
+      variant = thumbnail;
+      break;
+    }
     case Type::DialogPhoto: {
       DialogPhoto dialog_photo;
       parse(dialog_photo, parser);
@@ -96,15 +113,6 @@ void PhotoSizeSource::parse(ParserT &parser) {
       variant = sticker_set_thumbnail;
       break;
     }
-    case Type::Thumbnail: {
-      Thumbnail thumbnail;
-      parse(thumbnail.thumbnail_type, parser);
-      if (thumbnail.thumbnail_type < 0 || thumbnail.thumbnail_type > std::numeric_limits<uint8>::max()) {
-        parser.set_error("Wrong thumbnail type");
-      }
-      variant = thumbnail;
-      break;
-    }
     case Type::Empty:
       break;
   }
diff --git a/td/telegram/files/FileLocation.h b/td/telegram/files/FileLocation.h
index f8996f26..54fa72af 100644
--- a/td/telegram/files/FileLocation.h
+++ b/td/telegram/files/FileLocation.h
@@ -401,7 +401,7 @@ class FullRemoteFileLocation {
                                                                    photo().secret_, BufferSlice(file_reference_));
           case PhotoSizeSource::Type::Thumbnail: {
             auto &thumbnail = photo().source_.thumbnail();
-            switch (file_type_) {
+            switch (thumbnail.file_type) {
               case FileType::Photo:
                 return make_tl_object<telegram_api::inputPhotoFileLocation>(
                     photo().id_, photo().access_hash_, BufferSlice(file_reference_),
@@ -475,7 +475,7 @@ class FullRemoteFileLocation {
   // photo
   FullRemoteFileLocation(const PhotoSizeSource &source, int64 id, int64 access_hash, int32 local_id, int64 volume_id,
                          DcId dc_id, std::string file_reference)
-      : file_type_(source.file_type)
+      : file_type_(get_photo_size_source_file_type(source))
       , dc_id_(dc_id)
       , file_reference_(std::move(file_reference))
       , variant_(PhotoRemoteFileLocation{id, access_hash, volume_id, 0, local_id, source}) {