title: Typing problems URLSearchParams
body: <p>I have this code:</p>
  <pre><code>const paramsString = &quot;q=URLUtils.searchParams&amp;topic=api&quot;;
  const searchParams = new URLSearchParams(paramsString);
  const Search: string = searchParams.get(&quot;topic&quot;)?
  searchParams.get(&quot;topic&quot;):&quot;100&quot;;
  </code></pre>
  <p>I get this error:</p>
  <pre><code>Type 'string | null' is not assignable to type 'string'.
    Type 'null' is not assignable to type 'string'.
  </code></pre>