Container folder missing

It’s been hidden well before Mojave, but as with then, you can show it temporarily or permanently.

Hold Option and select Library from Go menu in Finder.

In the View Options for your home folder, check the box to show the Library.

The user Library is hidden by default. Likely because Apple doesn't trust the users to not muck it up.

If the Containers folder was missing, most everything would stop working. There isn't one in /Library.