title: .includes does not exist on type 'string[]'
body: <p>Trying to use .includes in my component.ts file but it throws me the following error. help me in resolving the issue.</p>
  
  <ul>
  <li>Error</li>
  </ul>
  
  <blockquote>
    <p>Property 'includes' does not exist on type 'string[]'</p>
  </blockquote>
  
  <ul>
  <li><p>app.component.ts </p>
  
  <pre><code>permissionCookie: string[]; 
  this.permissionCookie = cookieService.get("permissions").split(",");
  this.permissionFlag = this.permissionCookie.includes("22");
  </code></pre></li>
  <li><p>ts.config</p>
  
  <pre><code>{
    "compilerOptions": {
      "baseUrl": "",
      "declaration": false,
      "emitDecoratorMetadata": true,
      "experimentalDecorators": true,
      "lib": ["es6", "dom"],
      "mapRoot": "./",
      "module": "es6",
      "moduleResolution": "node",
      "outDir": "../dist/out-tsc",
      "sourceMap": true,
      "target": "es5",
      "typeRoots": [
        "../node_modules/@types"
      ]
    }
  }
  </code></pre>
  
  <p>this <a href="https://stackoverflow.com/questions/40545329/property-includes-does-not-exist-on-type-string">Property &#39;includes&#39; does not exist on type &#39;string[]&#39;</a> didnt help me either</p></li>
  </ul>