Send error message if downloading media from WhatsApp fails

portal.go

@@ -906,6 +906,12 @@ func (portal *Portal) HandleMediaMessage(source *User, download func() ([]byte,
 	data, err := download()
 	if err != nil {
 		portal.log.Errorfln("Failed to download media for %s: %v", info.Id, err)
+		resp, err := portal.MainIntent().SendNotice(portal.MXID, "Failed to bridge media")
+		if err != nil {
+			portal.log.Errorfln("Failed to send media download error message for %s: %v", info.Id, err)
+		} else {
+			portal.finishHandling(source, info.Source, resp.EventID)
+		}
 		return
 	}