{
  name = "Thread";
  rootViewer =
  {
    viewerType = "MmSplitView";
    orientation = "horizontal";
    children =
    (
      {
        viewerType = "MmBoxView";
        orientation = "vertical";
        defaultSize = 200;
        minWidth = 100;
        autoresize = 0;
        toggleMenuTitle = "Mailboxes";
        toggleKeyEquivalent = "^~@d";

        dragRect = { width = 16.0; height = 16.0; location = "bottomRight"; };

        children =
        (
          {
            identifier = "mailboxesOutline";
            viewerType = "MmMailboxesOutlineView";
            stickyMessages = 1;
          },
          {
            viewerType = "MmMailboxesStatusBar";
          },
        );
      },
      {
        viewerType = "MmSplitView";
        orientation = "vertical";
        collapsibleSubview = 2; // Incomplete support -- no way to get it back (1 = first, 2 = last)
        children =
        (
          {
            identifier = "pathOutlineBox";
            viewerType = "MmBoxView";
            orientation = "vertical";
            defaultSize = 250;
            autoresize = 0;
            children =
            (
              {
                identifier = "pathControl";
                viewerType = "MmPathControlView";
                sources = ( { sourceIdentifier = "mailboxesOutline"; } );
              },
              { viewerType = "MmSeparatorView"; showWithViews = ( "pathControl" ); },
              {
                viewerType = "MmSplitView";
                minHeight = 50;
                orientation = "horizontal";
                children =
                (
                  {
                    identifier = "mainOutline";
                    viewerType = "MmMessagesOutlineView";
                    // columnSettings = "outlineColumns";
                    sources = ( { sourceIdentifier = "pathControl"; } );
                    defaultSize = 350;
                  },
                  // {
                  //  identifier = "locator";
                  //  viewerType = "MmLocatorView";
                  //  sources = ( { sourceIdentifier = "mainOutline"; } );
                  //  canBecomeKeyView = 0; // Not implemented
                  // },
                );
              },
            );
          },
          {
            viewerType = "MmSplitView";
            orientation = "horizontal";
            children =
            (
              {
                viewerType = "MmBoxView";
                orientation = "vertical";
                defaultSize = 200;
                autoresize = 0;
                children =
                (
                  {
                    viewerType = "MmLabelView";
                    label = "Thread";
                  },
                  { viewerType = "MmSeparatorView"; },
                  {
                    identifier = "threadOutline";
                    viewerType = "MmMessagesOutlineView";
                    minWidth = 100;
                    sources = ( { sourceIdentifier = "mainOutline"; } );
                    selectionSources = ( { sourceIdentifier = "mainOutline"; } );
                    // FIXME: The transformation does not work 'per' message, i.e., it tries to combine any 'from' with any 'to' in $mainOutline.
                    transformation = "$ALL_MESSAGES.filter(#thread-id =[c] $mainOutline.#thread-id)";
                    defaultColumns = ( "subject", "relativeDate" );
                    outlineColumn = "subject";
                  },
                );

                //toggleMenuTitle = "Correspondence View";
                //toggleKeyEquivalent = "^~@c";
              },
              {
                viewerType = "MmBoxView";
                orientation = "vertical";
                children =
                (
                  {
                    identifier = "headersView";
                    viewerType = "MmHeadersView";
                    sources = ( { sourceIdentifier = "threadOutline"; } );
                    inject = ( "headersFormatting.plist" );
                  },
                  { viewerType = "MmSeparatorView"; showWithViews = ( "headersView" ); },
                  {
                    identifier = "tagsEditor";
                    viewerType = "MmTagsEditor";
                    sources = ( { sourceIdentifier = "threadOutline"; } );
                  },
                  { viewerType = "MmSeparatorView"; showWithViews = ( "tagsEditor" ); },
                  {
                    identifier = "blockingView";
                    viewerType = "MmImageBlockingView";
                    sources = ( { sourceIdentifier = "threadOutline"; } );
                    transformation = "$threadOutline.filter(##blocked-count exists)";
                  },
                  { viewerType = "MmSeparatorView"; showWithViews = ( "blockingView" ); },
                  {
                    identifier = "securityView";
                    viewerType = "MmSecurityView";
                    sources = ( { sourceIdentifier = "threadOutline"; } );
                    transformation = "$threadOutline.filter(##security-problem exists)";
                  },
                  { viewerType = "MmSeparatorView"; showWithViews = ( "securityView" ); },
                  {
                    identifier = "messageView";
                    viewerType = "MmWebView";
                    sources = ( { sourceIdentifier = "threadOutline"; } );
                    minWidth = 175;
                    minHeight = 50;
                  },
                );
              }
            );

            toggleMenuTitle = "Message View";
            toggleKeyEquivalent = "^~@h";
          },
          // {
          //  identifier = "messageEditor";
          //  viewerType = "MmMessageTextView";
          //  sources = ( { sourceIdentifier = "threadOutline"; } );
          //  minimumNumberOfMessages = 1;
          //  maximumNumberOfMessages = 1;
          //  match = "$threadOutline.filter(#flags.flag = '\\Draft')"; // Only match drafts
          // },
        );
      },
    );
  };
}