title: Autocomplete RichTextBox in .NET
body: <p>I am making a text editor and I want to make a autocomplete for the RichTextBox which the text is inside her, but I have no clue how to do this. I checked the internet and all of it is how to do it with a normal TextBox...</p>
  
  <p>I would really appreciate to get help with that if someone knows how to do it.</p>