FULL PRODUCT VERSION :
java version "1.8.0_121"
Java(TM) SE Runtime Environment (build 1.8.0_121-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.121-b13, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 10.0.14393]
MacOs Sierra 10.12.4

A DESCRIPTION OF THE PROBLEM :
When a tree node is expanded for the first time, and previously selected node lower down the screen is incorrectly redrawn.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Run the code provided.

Select a node.

Expand a node above it.

Wrong nodes are highlighted.

I have screen prints if you wish to see them.



EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Only one line should be highlighted
ACTUAL -
The correct line has an outline, the node two lines down is highlighted.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
package com.bytezone.bugs;

import java.io.File;

import javafx.application.Application;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.TreeTableColumn;
import javafx.scene.control.TreeTableView;
import javafx.scene.control.cell.TreeItemPropertyValueFactory;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;

public class BugApp extends Application
{
  private final BorderPane borderPane = new BorderPane ();

  private Parent createContent ()
  {
    TreeTableView<MyFile> table = new TreeTableView<> ();
    MyTreeItem root = new MyTreeItem (new MyFile (new File ("/")));
    table.setRoot (root);
    table.setShowRoot (false);

    TreeTableColumn<MyFile, String> fileNameColumn = new TreeTableColumn<> ("Filename");
    TreeTableColumn<MyFile, Long> sizeColumn = new TreeTableColumn<> ("Size");
    table.getColumns ().setAll (fileNameColumn, sizeColumn);

    fileNameColumn.setCellValueFactory (new TreeItemPropertyValueFactory ("name"));
    sizeColumn.setCellValueFactory (new TreeItemPropertyValueFactory ("length"));

    borderPane.setCenter (table);

    return borderPane;
  }

  @Override
  public void start (Stage primaryStage) throws Exception
  {
    primaryStage.setTitle ("Bug Application");
    primaryStage.setWidth (500);
    primaryStage.setScene (new Scene (createContent ()));
    primaryStage.show ();
  }

  public static void main (String[] args)
  {
    Application.launch (args);
  }
}

package com.bytezone.bugs;

import java.io.File;
import java.io.IOException;
import java.nio.file.DirectoryStream;
import java.nio.file.Files;
import java.nio.file.Path;

import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.control.TreeItem;

public class MyTreeItem extends TreeItem<MyFile>
{
  boolean firstTimeChild = true;
  boolean firstTimeLeaf = true;
  boolean isLeaf;

  public MyTreeItem (MyFile myFile)
  {
    super (myFile);
  }

  @Override
  public boolean isLeaf ()
  {
    return !getValue ().isDirectory ();
  }

  @Override
  public ObservableList<TreeItem<MyFile>> getChildren ()
  {
    if (firstTimeChild)
    {
      firstTimeChild = false;
      super.getChildren ().setAll (buildChildren (this));
    }
    return super.getChildren ();
  }

  private ObservableList<TreeItem<MyFile>> buildChildren (MyTreeItem treeItem)
  {
    ObservableList<TreeItem<MyFile>> children = FXCollections.observableArrayList ();

    try (DirectoryStream<Path> directoryStream =
        Files.newDirectoryStream (getValue ().getPath ()))
    {
      for (Path path : directoryStream)
      {
        File file = path.toFile ();
        if (Files.isDirectory (path) && !file.getName ().startsWith ("."))
          children.add (new MyTreeItem (new MyFile (file)));
      }
    }
    catch (IOException ex)
    {
      System.out.println ("oops");
    }
    return children;
  }
}

package com.bytezone.bugs;

import java.io.File;
import java.nio.file.Path;

import javafx.beans.property.LongProperty;
import javafx.beans.property.SimpleLongProperty;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;

public class MyFile
{
  private final File file;
  private StringProperty name;
  private LongProperty length;

  public MyFile (File file)
  {
    this.file = file;
    setName (file.getName ());
    setLength (file.length ());
  }

  public boolean isDirectory ()
  {
    return file.isDirectory ();
  }

  public Path getPath ()
  {
    return file.toPath ();
  }

  public void setName (String value)
  {
    nameProperty ().set (value.isEmpty () ? "root" : value);
  }

  public String getName ()
  {
    return nameProperty ().get ();
  }

  public StringProperty nameProperty ()
  {
    if (name == null)
      name = new SimpleStringProperty (this, "name");
    return name;
  }

  public void setLength (long value)
  {
    lengthProperty ().set (value);
  }

  public long getLength ()
  {
    return lengthProperty ().get ();
  }

  public LongProperty lengthProperty ()
  {
    if (length == null)
      length = new SimpleLongProperty (this, "length");
    return length;
  }
}
---------- END SOURCE ----------