Five years passed by and no one seconded this request??? I can’t believe this!

I am talking about something akin to Word’s AutoCorrect, albeit not with all the bells and whistles there. Just a simple substitute of a word (not part of a word!) as you type. An ESC would undo the substitution.

This is great in cases like this:
* Type an unlikely small string and it will be substituted by a (much longer) one;
* Substitute a string by a non-keyboard character, e.g., type << and it will be substituted by '«'

And there are many more!

Yes, all these can be done by current features too but the AutoCorrect is a lot easier and intuitive!