Set forwarded flag on cross account move

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

@@ -307,8 +307,8 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
 
     // https://www.iana.org/assignments/imap-jmap-keywords/imap-jmap-keywords.xhtml
     private static final List<String> IMAP_KEYWORDS_BLACKLIST = Collections.unmodifiableList(Arrays.asList(
+            MessageHelper.FLAG_FORWARDED.toLowerCase(Locale.ROOT),
             "$MDNSent".toLowerCase(Locale.ROOT), // https://tools.ietf.org/html/rfc3503
-            "$Forwarded".toLowerCase(Locale.ROOT),
             "$SubmitPending".toLowerCase(Locale.ROOT),
             "$Submitted".toLowerCase(Locale.ROOT),
             "$Junk".toLowerCase(Locale.ROOT),
@@ -1131,7 +1131,7 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
 
             ibSnoozed.setVisibility(message.ui_snoozed == null && !message.ui_unsnoozed ? View.GONE : View.VISIBLE);
             ivAnswered.setVisibility(message.ui_answered ? View.VISIBLE : View.GONE);
-            ivForwarded.setVisibility(message.hasKeyword("$Forwarded") ? View.VISIBLE : View.GONE);
+            ivForwarded.setVisibility(message.isForwarded() ? View.VISIBLE : View.GONE);
             ivAttachments.setVisibility(message.attachments > 0 ? View.VISIBLE : View.GONE);
 
             if (viewType == ViewType.FOLDER)

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

@@ -870,7 +870,7 @@ class Core {
             throw new IllegalArgumentException("keyword/uid");
 
         if (!ifolder.getPermanentFlags().contains(Flags.Flag.USER)) {
-            if ("$Forwarded".equals(keyword) && false) {
+            if (MessageHelper.FLAG_FORWARDED.equals(keyword) && false) {
                 JSONArray janswered = new JSONArray();
                 janswered.put(true);
                 onAnswered(context, janswered, folder, message, ifolder);
@@ -1031,10 +1031,21 @@ class Core {
 
             imessage.saveChanges();
 
-            imessage.setFlag(Flags.Flag.SEEN, message.ui_seen);
-            imessage.setFlag(Flags.Flag.ANSWERED, message.ui_answered);
-            imessage.setFlag(Flags.Flag.FLAGGED, message.ui_flagged);
-            imessage.setFlag(Flags.Flag.DELETED, message.ui_deleted);
+            if (flags.contains(Flags.Flag.SEEN))
+                imessage.setFlag(Flags.Flag.SEEN, message.ui_seen);
+            if (flags.contains(Flags.Flag.ANSWERED))
+                imessage.setFlag(Flags.Flag.ANSWERED, message.ui_answered);
+            if (flags.contains(Flags.Flag.FLAGGED))
+                imessage.setFlag(Flags.Flag.FLAGGED, message.ui_flagged);
+            if (flags.contains(Flags.Flag.DELETED))
+                imessage.setFlag(Flags.Flag.DELETED, message.ui_deleted);
+
+            if (flags.contains(Flags.Flag.USER)) {
+                if (message.isForwarded()) {
+                    Flags fwd = new Flags(MessageHelper.FLAG_FORWARDED);
+                    imessage.setFlags(new Flags(fwd), true);
+                }
+            }
         }
 
         db.message().setMessageRaw(message.id, true);

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

@@ -300,6 +300,10 @@ public class EntityMessage implements Serializable {
         return false;
     }
 
+    boolean isForwarded() {
+        return hasKeyword(MessageHelper.FLAG_FORWARDED);
+    }
+
     String checkReplyDomain(Context context) {
         if (from == null || from.length == 0)
             return null;

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

@@ -121,6 +121,7 @@ public class MessageHelper {
     static final int SMALL_MESSAGE_SIZE = 192 * 1024; // bytes
     static final int DEFAULT_DOWNLOAD_SIZE = 4 * 1024 * 1024; // bytes
     static final String HEADER_CORRELATION_ID = "X-Correlation-ID";
+    static final String FLAG_FORWARDED = "$Forwarded";
 
     private static final int MAX_MESSAGE_SIZE = 10 * 1024 * 1024; // bytes
     private static final long ATTACHMENT_PROGRESS_UPDATE = 1500L; // milliseconds

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

@@ -714,7 +714,8 @@ public class ServiceSend extends ServiceBase implements SharedPreferences.OnShar
             if (message.wasforwardedfrom != null) {
                 List<EntityMessage> forwardeds = db.message().getMessagesByMsgId(message.account, message.wasforwardedfrom);
                 for (EntityMessage forwarded : forwardeds)
-                    EntityOperation.queue(this, forwarded, EntityOperation.KEYWORD, "$Forwarded", true);
+                    EntityOperation.queue(this, forwarded,
+                            EntityOperation.KEYWORD, MessageHelper.FLAG_FORWARDED, true);
             }
 
             // Update identity