ok so for my rich text editor I think what I need is:

• icons for each rich text command (this will be somewhere in between a WYSIWYG editor and a markup editor)
• a way to query what position within the rich text is closest to the mouse cursor
• a way to query where the edge of a letter is for drawing the edit cursor
• probably grab all the Godot TextEdit and LineEdit code and see if I can reuse it for the keyboard controls

that doesn't seem too bad