ses--advice-copy-region-as-kill

ses--advice-copy-region-as-kill is a compiled Lisp function in `ses.el'.

(ses--advice-copy-region-as-kill CRAK-FUN BEG END &rest ARGS)

It doesn't make sense to copy read-only or intangible attributes into the
kill ring. It probably doesn't make sense to copy keymap properties.
We'll assume copying front-sticky properties doesn't make sense, either.

This advice also includes some SES-specific code because otherwise it's too
hard to override how mouse-1 works.