Not removing ** when using __ for Italic or Bold

Hi, when I want to undo the Bold-ness using Ctrl+B or Ctrl-I it only removes the currently selected characters. 
I would like to toggle also the other character, e.g. for undoing or converting existing bold Text, so 

Before: `**text**` 
After 1st Ctrl+B:  `text` 
After 2nd Ctrl+B:  `__text__` 

What do you think?