I think you meant to update a different ticket, your response has nothing to do with the question asked.

It's 2 months old and I no longer work on the affected project so I can't verify if a solution has been provided yet, but you can see this was replicated by @Arkadiusz Idzikowski already.

At no point do you reference autocomplete in your response. The question is specific to autocomplete functionality. Where at the time of asking if you specify updateOn: 'submit' for the formControl of the autocomplete then the autocomplete will not function correctly (does not drop down, populate, etc) but if you leave it unset it is fine.

I assume your success/error messages are being rendered conditionally like this:

<mdb-error *ngIf="input?.invalid && (input?.dirty || input?.touched)"
      >Input value is required</mdb-error
    >
    <mdb-success *ngIf="input?.valid && (input?.dirty || input?.touched)"
      >Looks good!</mdb-success
    >

Validation problem with untouched input should be resolved via adding onSubmit method in which markAllAsTouched() should be executed on the FormGroup. Here is an example:

template:

<form [formGroup]="validationFormGroup" (ngSubmit)="onSubmit()">
 ...
</form>

component.ts:

export class ValidationComponent {
  ...
  onSubmit(): void {
    this.submitValidationForm.markAllAsTouched();
  }
}