The "Remember me" functionality will be removed, see:
For backwards compatibility, the new SimpleLoginPlugin from CMS 10.0,
CMS7-8957, will be backported for the next CMS 7.9 maintenance release.
The existing RememberMePlugin will be re-implemented by just and only extending this new SimpleLoginPlugin, possibly needing to retain the relevant RememberMePlugin (name) translation properties.
Furthermore, the RememberMePlugin must be marked as @Deprecated and no longer available as of CMS 10.0.