Either a bug in the docs or a missing feature but....
Currently it appears as though the options section in a declarative pipeline is global to all uses of the pipeline.
However a very common use case is to have a different artifact retention strategy for PRs vs mainline branches.
According to the docs it does not seem like this is possible to do, so this
This RFE is to update the documentation to show how it is done, or add support for this kind of use case (different options per something)
 may be branch vs PR, could be branch names (master and stable may be considered special) etc...