Google search in a chrome extension

Question

I'm trying to create an extension where I can do a one-word google search.

This is the manifest:

{
    "manifest_version": 2,
    "name": "GoogleSearch",
    "description": "GoogleSearch",
    "version": "1.0",
    "browser_action":{
        "default_popup": "popup.html",
        "default_title": "GoogleSearch"
    },
    "permissions": ["tabs"]
}

And this is the part of the code in the popup.html I couldn´t make it work:

<input type="text" class="form-control" id="inputWord" placeholder="Word">
<button id ="btn" onclick="doSearch()">Search</button>
<script>
 function doSearch() {
  let word = document.querySelector('#inputWord').value;
  window.open("https://www.google.com.uy/search?q=" + word);
 }
</script>

So when I click the button, nothing happens.