Use MDN original message ID

app/src/main/java/eu/faircode/email/Core.java

@@ -4198,9 +4198,20 @@ class Core {
                             if (s != null)
                                 map.put(s.id, s);
 
-                            List<EntityMessage> reported = db.message().getMessagesByMsgId(folder.account, message.inreplyto);
+                            List<EntityMessage> all = new ArrayList<>();
-                            if (reported != null)
+
-                                for (EntityMessage m : reported)
+                            if (message.inreplyto != null) {
+                                List<EntityMessage> replied = db.message().getMessagesByMsgId(folder.account, message.inreplyto);
+                                if (replied != null)
+                                    all.addAll(replied);
+                            }
+                            if (r.refid != null) {
+                                List<EntityMessage> refs = db.message().getMessagesByMsgId(folder.account, r.refid);
+                                if (refs != null)
+                                    all.addAll(refs);
+                            }
+
+                            for (EntityMessage m : all)
                                 if (!map.containsKey(m.folder)) {
                                     EntityFolder f = db.folder().getFolder(m.folder);
                                     if (f != null)

app/src/main/java/eu/faircode/email/MessageHelper.java

@@ -4541,6 +4541,7 @@ public class MessageHelper {
         String status;
         String diagnostic;
         String disposition;
+        String refid;
         String html;
 
         Report(String type, String content) {
@@ -4596,6 +4597,9 @@ public class MessageHelper {
                             case "Disposition":
                                 this.disposition = value;
                                 break;
+                            case "Original-Message-ID":
+                                this.refid = value;
+                                break;
                         }
                     }
                 }