Note Toolbar is the bar that appears just above the sticky note when you move the mouse over the sticky note.
When there are many desktop sticky notes, you may find this automatic appearance of note toolbar a little annoying. You may prefer to see the note toolbar only when you click on specific sticky note.
You can change this behavior using Notezilla’s preferences. Just go to the Notes Browser and choose Advanced->Preferences menu. In the preferences window, change “Show note toolbar on” options (mouse click or mouse hover or Ctrl key + mouse hover) as per your preferences.