Changing the internals of FP OT model is too involved for me unfortunately. Also I don’t think bookmarks will work as sentinels as it is essential for them to behave like invisible text.
“Collapsed ranges represent text”, well they represent collapsed text, which to me as a user you don’t expect to suddenly appear when you paste it somewhere else.
Also the behavior in the plunkr above is confusing. The first collapsed range is not copied (I guess because it is not ‘selected’) where as the other two do.
Basically, I am asking if it is possible to have a way to created collapsed ranges which do not get copied to the clipboard ? that would be very helpful and intuitive.