(and various other lockfile upgrades. "npm audit" is clean.)
The date picker to use with 4.0 is unmaintained, and the new one is
apparently quite different.
Given that 5.0 is expected to be released this quarter, I prefer to
jump straight to the new one and get things working with it, even if
it means using an alpha in the short-term.
Besides being more clear about what belongs to which, this helps with
docker caching. The server and ui parts are only rebuilt when their
respective subdirectories change.
Extend this a bit further by making the webpack build not depend on
the target architecture. And adding cache dirs so parts of the server
and ui build process can be reused when layer-wide caching fails.
