Error: This constructor is not compatible with Angular Dependency Injection in Angular when using FormBuilder in constructor

🐛 bug report

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Description of the problem

Angular codesandbox throws dependency injection error when using FormBuilder API.

The error

This constructor is not compatible with Angular Dependency Injection because its dependency at index 0 of the parameter list is invalid.
This can happen if the dependency type is a primitive like a string or if an ancestor of this class is missing an Angular decorator.


Please check that 1) the type for the parameter at index 0 is correct and 2) the correct Angular decorators are defined for this class and its ancestors.

How has this issue affected you? What are you trying to accomplish?

Not able to create Angular sandbox using reactive forms.

To Reproduce

Link to sandbox: [link]

Your Environment

Start with the linked CodeSandbox reproduction, especially src/app/app.component.ts, and verify the reported Angular Dependency Injection error when using FormBuilder. Trace whether the failure is reproducible in the project and identify the relevant integration entry point. Done means the sandbox can create an Angular reactive form without the constructor compatibility error.