title: Mouse cursor disappears when textbox at ToolStripDropDown editing
body: <p>I have a user control with RichTextBox and two buttons on it. I'm trying to show that at ToolStripDropDown on ToolStripButton click. I'm using ToolStripControlHost to put my control at ToolStripDrowDown. When I click ToolStripButton at form toolbar, I show dropdown at some position and make focus at ToolStripControlHost control. Mouse pointer stays above ToolStripButton and cursor is at RichTextBox. But when I start editing RichTextBox mouse pointer disappears and I can see it only when it's out of form rectangle. How can I fix it?</p>
  
  <p>Here is my code:</p>
  
  <pre><code>private void toolBtnNote_Click(object sender, EventArgs e)
  {
  
     dropDownClosed = false;
     noteChanged = false;
  
     tsdd = new ToolStripDropDown();
     this.tsdd.Opened += new EventHandler(tsdd_Opened);
     this.tsdd.AutoSize = true;
  
     NoteEdit ne = new NoteEdit();
     ne.NoteText = note ?? "";
     // appears when user clicks first button at my control
     ne.OkClick += new NoteEdit.NoteEditEvent(ne_OkClick);
     // appears when user clicks second button at my control
     ne.CancelClick += new NoteEdit.NoteEditEvent(ne_CancelClick);
  
     this.tbh = new ToolStripControlHost(ne, "noteEdit");
     this.tbh.Padding = new Padding(0);
     this.tbh.AutoSize = false;
     this.tbh.Size = ne.Size;
  
     this.tsdd.Items.Add(tbh);
     this.tsdd.Padding = new Padding(0);
     this.tsdd.Closing += new ToolStripDropDownClosingEventHandler(tsdd_Closing);
     // show toolstripdrowdown at specific position at DataGridView         
     this.tsdd.Show(dgvMarks, cellRect.Location + new Size(0, cellRect.Height));
  
     while (!this.dropDownClosed)
     {
         Application.DoEvents();
     }
  
     if(noteChanged) {...}
  }
  
  void ne_CancelClick()
  {
      tsdd.Close();
  }
  
  void ne_OkClick()
  {
      noteChanged = true;
      tsdd.Close();
  }
  
  void tsdd_Opened(object sender, EventArgs e)
  {
      tbh.Focus();
  }
  
  void tsdd_Closing(object sender, ToolStripDropDownClosingEventArgs e)
  {
      dropDownClosed = true;
  }
  </code></pre>