Error:- NG9: Property 'files' does not exist on type 'EventTarget'.

[fervent snow]

I was creating a file upload component.
https://stackblitz.com/edit/stackblitz-starters-7rtzbt?file=src%2Fapp%2Ffile-upload%2Ffile-upload.component.ts

I have been through::->

1. https://blog.angular-university.io/angular-file-upload/
2. https://stackoverflow.com/questions/43176560/property-files-does-not-exist-on-type-eventtarget-error-in-typescript
3. https://stackoverflow.com/questions/47936183/angular-file-upload

import { Component } from '@angular/core';

interface HTMLInputEvent extends Event {
    target: HTMLInputElement & EventTarget;
}

@Component({
  selector: 'app-file-upload',
  standalone: true,
  imports: [],
  templateUrl: './file-upload.component.html',
  styleUrl: './file-upload.component.css'
})
export class FileUploadComponent {

  onFileSelected(event:HTMLInputEvent) {

    const file:File|null  = event.target!.files!.item(0);

    if (file) {
      console.log(file);
      const formData = new FormData();
      formData.append("file1", file);
      console.log(formData);
    }
  }
}

[rare turret]

You know that the target is an HTMLInputElement, so tell TypeScript:
(event.target as HTMLInputElement).files.items(0)