title: Uncaught Error occured - 'mat-icon' is not a known element:
body: <p>The error occurred while running.</p>
  
  <pre><code>Unexpected value 'MatIconRegistry' imported by the module 'AppModule'. 
  Please add a @NgModule annotation
  </code></pre>
  
  <p>How to solve this error. I added the "@angular/material" in app.module.ts. Still, it's thrown an error.</p>