How do I record new midi notes to an existing midi part?

For example I have some midi part I want to refill. I want to hear old notes and record new notes, using the same instrument. It’s not comfortable to make a new track, load the same instrument (especially for hard instruments) and record. Is it possible to record new notes in the same midi event with hearing old and recording notes? If no, what suggestion to do?
Thanks.

It’s not yet possible.

one common solution: Use 2 midi tracks.

The first one will serve as “MIDI Bus” it will have the instrument plugin and you’ll never record to it. Set it to monitor “In” explicitly.
The 2nd Track one will hold the actual data that you record and not have an instrument plugin (midi in, midi out). Set it to monitor “Disk” .

Now, connect your keyboard to both channels. And connect Track2 out -> Track 1 in. et voila.

PS. I meant to say “connect your keyboard to both tracks”.

It will directly trigger the Synth on Track1. It will be recorded (but not passed though) on Track2. Existing notes on Track 2 will be played (disk monitor) and reach the synth as well.

Big thanks, @x42!
Must be comfortable idea. I’ll try. I didn’t think about midi bus, it’s interesting to test)
Just one more question.
If I’ll record few leyers of midi, can I consolidate them after? Or must only copy notes from a new layer to an old one?

You can’t consolidate MIDI regions. You can bounce a time selection, which is similar (but involves creating a new file on disk).

Thanks, Paul!
I’ve tasted it - works). It’s not a problem to have some more midi files in session folder, if you mean that. I’ve no regret about few waste bytes HDD.