diff --git a/portal.go b/portal.go
index bce80d7..dbbc2c6 100644
--- a/portal.go
+++ b/portal.go
@@ -986,11 +986,6 @@ func (portal *Portal) HandleMediaMessage(source *User, download func() ([]byte,
 		return
 	}
 
-	// WhatsApp sends incorrect mime types 3:<
-	if detected := http.DetectContentType(data); detected != "application/octet-stream" {
-		mimeType = detected
-	}
-
 	// synapse doesn't handle webp well, so we convert it. This can be dropped once https://github.com/matrix-org/synapse/issues/4382 is fixed
 	if mimeType == "image/webp" {
 		img, err := webp.Decode(bytes.NewReader(data))