Clipboard manager for Linux that allows selective copy to the clipboard manager?

Is there a clipboard manager that actually allows selective copying to the clipboard manager, such as by pressing some special key when copying to the clipboard, instead of copying all copied text to the clipboard manager? Thanks

Welcome @user12 ,
A lot of clipboard managers are tied to a particular desktop environment.
The one that seems to be platform independent is copyq
It seems to have keyboard shortcuts and that might be what you are looking for.
It is available as the copyq package in Debian
More info here

Regards
Neville