While I was using my code, I noticed that my extension was not updating the DOM after the digest cycle of AngularJS. Of course it had to be fixed.
Basically I just had to wrap my previous code into Angular’s digest cycle ($scope) watcher and that was it.
I also fixed the additional AngularJS-nl2br snippet, as it was not breaking the newlines very well.
And as usually – the snippet can be found on my GitHub