if items contain multi channel events, editing or simply selecting within
active mode channel filter other then ALL Channels, deletes all REAPER Notation Meta at the other channels.
1. Draw a few events at ch 1 or with All Channels,
make a slur, note heads or whatever, change to ch 2, draw one or more events or selection, go back to All channels or ch1..
REAPER Notation Meta is deleted
As long you don´t click into the edit area after swapping the channel filter all is fine..
If you make a selection or whatever and went back all REAPER Notation deletes..
and it could be that also all other events gone.
I think something is wrong with the filter because the same "delete behavior" is happen within list view.
notation & list view multi channel editing/filter is broken
little example here: (list view example is shorter^^)
a little notation view example
Working with this behavior is for me a little bit impossible..
You have to change only from ALL Channel to whatever ch>1 make a selection and REAPER Meta data is gone..
The Only Filter which is safe is ALL CHANNEL view