Errors began after updating to Angular-Cli V10.1.0. Initial problems I encountered: The ng command was not working. I found that core dependencies were missing:
symfony-finder
jamvm
google-fonts
sf-symbols
default-initialization
indirection
authorization-server
ptv-vissim
kimball
essbase
mappings
mailgun
disco
adaptive-cards
react-native-deck-swiper
django-admin
office-ui-fabric-react
hmac
gtkmm3
rakudo
qqmlengine
hamiltonian-path
secret-manager
logits
angularjs-controller
searchkit
vuepress
transformer
firefox-driver
networkimageview