diff --git a/ts/jobs/helpers/sendNormalMessage.ts b/ts/jobs/helpers/sendNormalMessage.ts
index be77c094d..d224fd990 100644
--- a/ts/jobs/helpers/sendNormalMessage.ts
+++ b/ts/jobs/helpers/sendNormalMessage.ts
@@ -31,7 +31,7 @@ import type {
   AttachmentWithHydratedData,
 } from '../../types/Attachment';
 import { copyCdnFields } from '../../util/attachments';
-import { LONG_MESSAGE, MIMETypeToString } from '../../types/MIME';
+import { LONG_MESSAGE } from '../../types/MIME';
 import type { RawBodyRange } from '../../types/BodyRange';
 import type {
   EmbeddedContactWithHydratedAvatar,
@@ -796,7 +796,7 @@ async function uploadMessageQuote({
         const uploaded = await uploadAttachment(thumbnail);
 
         return {
-          contentType: MIMETypeToString(thumbnail.contentType),
+          contentType: attachment.contentType,
           fileName: attachment.fileName,
           thumbnail: uploaded,
         };