Plasma 5 is a whole new version and won't co-install with Plasma 1. Nevertheless some parts of runtime should co-install so apps using kdelibs4 can run under Plasma 5.
these are new version of the KDELibs 4 equivalents from kde-workspace and won't co-install, no change expected
- kwin is now co-installable
- baloo libraries are co-installable but not the binaries (although they are drop in replacements)
- kfilemetadata co-installable library version