Notes for tactics trainer

I'd like a notes feature on the tactics trainer.  While notes on live games live on in the game, that wouldn't work on the trainer, as games go by and aren't saved.

i'd like to make notes about common mistakes I'm making so I can keep track of my progress and remind myself what I need more work on.   No technical difficulty here - just a place for notes.   I'm keeping them on pen and paper for now.

Not sure I get it... Is a "Note" linked to a particular problem?

No, a note not attached to a particular problem, but to the trainer itself.  I believe we already have notes on individual games.   

I'm finding myself failing on certain types of problems.  I'd like to keep notes online about this.