The core set the MetaPackageCores|meta-package pack attaches from its .onAttach hook at version (the newest release's when unknown, the oldest one's for a version predating every recorded release), empty for any other package.
pack
.onAttach
version
Optional
The core set the MetaPackageCores|meta-package
packattaches from its.onAttachhook atversion(the newest release's when unknown, the oldest one's for a version predating every recorded release), empty for any other package.