ng add fails to work with Angular 11.1.x

I’m submitting a…

[ ] Regression (a behavior that used to work and stopped working in a new release)
[x] Bug report
[ ] Performance issue
[ ] Feature request
[ ] Documentation issue or request
[ ] Support request
[ ] Other... Please describe:

Current behavior

After running ng add command it throws an exception and doesn’t do the work successfully.

Expected behavior

It would finish the process.

Minimal reproduction of the problem with instructions

After updating angular-cli to latest create a new project with ng new command and then run the ng add @ngneat/tailwind command in the folder. It would crash with below message:

An unhandled exception occurred: Cannot find module '@schematics/angular/utility/config'
Require stack:
- /Users/xxxxxxxx/node_modules/@ngneat/tailwind/src/utils/normalize-options-ng.js
- /Users/xxxxxxxx/node_modules/@ngneat/tailwind/src/schematics/ng-add/ng-add.js
- /Users/xxxxxxxx/node_modules/@angular-devkit/schematics/tools/export-ref.js
- /Users/xxxxxxxx/node_modules/@angular-devkit/schematics/tools/index.js
- /Users/xxxxxxxx/node_modules/@angular/cli/utilities/json-schema.js
- /Users/xxxxxxxx/node_modules/@angular/cli/models/command-runner.js
- /Users/xxxxxxxx/node_modules/@angular/cli/lib/cli/index.js
- /usr/local/lib/node_modules/@angular/cli/lib/init.js
- /usr/local/lib/node_modules/@angular/cli/bin/ng
See "/private/tmp/ng-jz5Ggc/angular-errors.log" for further details.

What is the motivation / use case for changing the behavior?

I think this is a compatibility issue with newer version of angular.

Environment

Angular version: 11.1.x

Browser:
- [ ] Chrome (desktop) version XX
- [ ] Chrome (Android) version XX
- [ ] Chrome (iOS) version XX
- [ ] Firefox version XX
- [x] Safari (desktop) version XX
- [ ] Safari (iOS) version XX
- [ ] IE version XX
- [ ] Edge version XX
 
For Tooling issues:
- Node version: 15.3.0
- Platform:  Mac

[vltansky]

I agree, but I think we should at least mention this in readme.

[vltansky]

There is also a difference in dependencies that we need to install for different angular versions: > v11.1 - only tailwindcss and selected plugins < v11.1 - postcss 8 < v11 - postcss 8, postcss-import, postcss-loader, autoprefixer