anchor.diff:      [<MethodImpl(MethodImplOptions.NoInlining)>]
       let LinkPrevElement (el: Node) children =
           InsertDoc (el.ParentNode :?> _) children (DU.BeforeNode el) |> ignore
  +
  +    /// Invokes and clears an element's afterRender callback(s).
  +    let AfterRender (el: DocElemNode) =
  +        match el.Render with
  +        | None -> ()
  +        | Some f -> f el.El; el.Render <- None
   
       /// Synchronizes the document (deep).
       let Sync doc =
           let rec sync doc =
               match doc with
               | AppendDoc (a, b) -> sync a; sync b
  -            | ElemDoc el -> SyncElement el; sync el.Children
  +            | ElemDoc el -> SyncElement el; sync el.Children; AfterRender el
               | EmbedDoc n -> sync n.Current
               | EmptyDoc
               | TextNodeDoc _ -> ()
  
positive.code:     let SyncElemNode el =
          SyncElement el
          Sync el.Children
  
      /// A set of node element nodes.
      type NodeSet =
  
negative.code:         Attrs.Sync el.El el.Attr
          if hasDirtyChildren el then
              DoSyncElement el
  
      /// Links an element to children by inserting them.
      [<MethodImpl(MethodImplOptions.NoInlining)>]
  