This error appears also when simply by mistake input
is placed out of the mat-form-field
. To fix it just bring it inside like below:
Bad code:
<mat-form-field class="full-width">
</mat-form-field>
<input matInput placeholder="Title" formControlName="title" #title />
Fix:
<mat-form-field class="full-width">
<input matInput placeholder="Title" formControlName="title" #title />
</mat-form-field>