Also ack with XEP-0184 read receipts for outgoing messages

xmpp/gateway/gateway.go

@@ -144,6 +144,7 @@ func sendMessageWrapper(to string, from string, body string, id string, componen
 			message.Extensions = append(message.Extensions, stanza.MarkReceived{ID: marker.Id})
 		} else if marker.Type == MarkerTypeDisplayed {
 			message.Extensions = append(message.Extensions, stanza.MarkDisplayed{ID: marker.Id})
+			message.Extensions = append(message.Extensions, stanza.ReceiptReceived{ID: marker.Id})
 		}
 	}
 	if !isCarbon && toJid.Resource != "" {

xmpp/handlers.go

@@ -461,6 +461,7 @@ func handleGetDiscoInfo(s xmpp.Sender, iq *stanza.IQ) {
 	if ok {
 		disco.AddIdentity("", "account", "registered")
 		disco.AddFeatures(stanza.NSMsgChatMarkers)
+		disco.AddFeatures(stanza.NSMsgReceipts)
 	} else {
 		disco.AddIdentity("Telegram Gateway", "gateway", "telegram")
 		disco.AddFeatures("jabber:iq:register")