From d479442a63963154dbc82511dcad5698410bafb6 Mon Sep 17 00:00:00 2001
From: John Preston <johnprestonmail@gmail.com>
Date: Thu, 4 Jul 2019 11:04:12 +0200
Subject: [PATCH] Fix local thumbnail saving for stickers.

---
 Telegram/SourceFiles/data/data_session.cpp | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/Telegram/SourceFiles/data/data_session.cpp b/Telegram/SourceFiles/data/data_session.cpp
index c32ae05ef..c0bf619ac 100644
--- a/Telegram/SourceFiles/data/data_session.cpp
+++ b/Telegram/SourceFiles/data/data_session.cpp
@@ -2328,15 +2328,20 @@ not_null<DocumentData*> Session::processDocument(
 
 	case mtpc_document: {
 		const auto &fields = data.c_document();
+		const auto mime = qs(fields.vmime_type);
+		const auto format = (mime == qstr("image/webp")
+			|| mime == qstr("application/x-tgsticker"))
+			? "WEBP"
+			: "JPG";
 		return document(
 			fields.vid.v,
 			fields.vaccess_hash.v,
 			fields.vfile_reference.v,
 			fields.vdate.v,
 			fields.vattributes.v,
-			qs(fields.vmime_type),
+			mime,
 			ImagePtr(),
-			Images::Create(std::move(thumb), "JPG"),
+			Images::Create(std::move(thumb), format),
 			fields.vdc_id.v,
 			fields.vsize.v,
 			StorageImageLocation());