Ionic problem: [ng]Schema validation failed with the following errors:[ng]Data path“.builders['app-shell']”should have required property 'class'

Question

affter I update the ionic4 to ionic5 and try to run the ionic app the server is broken and show me this Error :

[ng] Schema validation failed with the

Answer 1

This worked for me as well,

1. npm uninstall @angular-devkit/build-angular
2. npm install @angular-devkit/build-angular@0.12.4