Agreed, but the extensibility is very limited. Just look at the contortions this little package has to go through to apply a color to portions of text: https:

Agreed, but the extensibility is very limited. Just look at the contortions this little package has to go through to apply a color to portions of text: https://github.com/Monnoroch/ColorHighlighter/blob/master/ColorHighlighter.py#L507 https://github.com/Monnoroch/ColorHighlighter/blob/master/Co... It has to create and apply a fake theme merged with your current theme so colors can be added "dynamically"[1]. The ancient Emacs (I hate a hate/love relationship with it) can do this is several ways, the "modern" one are overlays IIRC. [1] As expected, this will lead to bugs related to the users' color schemes: https://github.com/Monnoroch/ColorHighlighter/issues https://github.com/Monnoroch/ColorHighlighter/issues