From 5224f71303b2201f7a744f74241d16d805cba5f1 Mon Sep 17 00:00:00 2001
From: Chocobozzz <me@florianbigard.com>
Date: Wed, 12 Feb 2020 10:26:35 +0100
Subject: [PATCH] Correctly check remote extension

---
 server/lib/activitypub/actor.ts | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/server/lib/activitypub/actor.ts b/server/lib/activitypub/actor.ts
index 8c5c618fc..fd934443b 100644
--- a/server/lib/activitypub/actor.ts
+++ b/server/lib/activitypub/actor.ts
@@ -221,9 +221,15 @@ function getAvatarInfoIfExists (actorJSON: ActivityPubActor) {
 
   if (!icon || icon.type !== 'Image' || !isActivityPubUrlValid(icon.url)) return undefined
 
-  const extension = icon.mediaType
-    ? mimetypes.MIMETYPE_EXT[icon.mediaType]
-    : extname(icon.url)
+  let extension: string
+
+  if (icon.mediaType) {
+    extension = mimetypes.MIMETYPE_EXT[icon.mediaType]
+  } else {
+    const tmp = extname(icon.url)
+
+    if (mimetypes.EXT_MIMETYPE[tmp] !== undefined) extension = tmp
+  }
 
   if (!extension) return undefined
 
-- 
2.25.1