These remain linked, so data remains to be read/loaded from the packed
version from the library (making this a useless and wasteful
duplication, also changes could be perceived as lost)
Continuation of !122092 which came up in #122033 -- but spread to more
operators / API so it is consistent everywhere
For operators, first intuition was to do it in a poll function, but that
isnt possible because the actual ID might depend on a given (to the
operator) ID name.
NOTE: Still not 100% in which scenarios linked data could still be
editable, but using ID_IS_EDITABLE for this now.
c6aa1fec2b / 918d34a9ed are related
Pull Request: https://projects.blender.org/blender/blender/pulls/122204
a65df02031