Can't delete file from cache in Safari

Question

In an Angular 6 application I'm using the Cache API to be able to store and delete an MP3 file.

In Safari, when trying to delete the file it doesn't get deleted and I receive a "Quota Exceeded" error message (in Chrome it works well).

I created an Example Angular Firebase App so that you can see the problem.

Example App code repository

Steps to reproduce the problem:

1. Open Safari (mobile or on a Mac computer)
2. Click on "Save file" button
3. Click on "Remove file" (the file should be removed but it is not)
4. Click on "Save file" again and you'll get the "Quota Exceeded" message.

Can anyone help me to see what is wrong with my code?

The method I call to delete the file is removeFile()

app.component.ts

import { Component, OnInit } from '@angular/core';
import { DomSanitizer } from '@angular/platform-browser';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent implements OnInit {

  // Omitted ...

  saveFile() {
    this.resetValues();  
    caches.open(this.id).then((cache) => {
      console.log("open complete", cache);
      return fetch(this.url).then((response) => {
        console.log("fetch complete", response);
        return cache.put(this.url, response).then((data) => {
          console.log("cache complete", data)
          this.status = 'File saved';
        });
      })
    }).catch((error: Error) => {
      this.errorMessage = error.message;
      console.error('Error caching file!', error);
    });
  }

  removeFile() {
    this.resetValues();
    caches.delete(this.id).then((cacheDeleted) => {
      console.log("File removed from cache:", cacheDeleted);
      this.status = 'File removed';
    }).catch((error: Error) => {
      this.errorMessage = error.message;
      console.error('Error removing file from cache :(', error);
    });
  }

}

package.json

{
  // Omitted ...
  "dependencies": {
    "@angular/animations": "^6.0.0",
    "@angular/common": "^6.0.0",
    "@angular/compiler": "^6.0.0",
    "@angular/core": "^6.0.0",
    "@angular/forms": "^6.0.0",
    "@angular/http": "^6.0.0",
    "@angular/platform-browser": "^6.0.0",
    "@angular/platform-browser-dynamic": "^6.0.0",
    "@angular/router": "^6.0.0",
    "core-js": "^2.5.4",
    "rxjs": "^6.0.0",
    "zone.js": "^0.8.26"
  },
  "devDependencies": {
    "@angular/compiler-cli": "^6.0.0",
    "@angular-devkit/build-angular": "~0.6.1",
    "typescript": "~2.7.2",
    "@angular/cli": "~6.0.1",
    "@angular/language-service": "^6.0.0",
    // Omitted ...
  }
}