Bootstrap 4.2.1 - Failed to execute 'querySelector' on 'Document': '[removed]void(0);' is not a valid selector

Question

I am working on a project which I started building on bootstrap 4.0.0. During this project, I had updated bootstrap regulary whenever the new versions ( 4.1.0

Answer 1

A suggestion:

Remove the empty href attribute & add cursor:pointer style to make A element clickable.

#dropdownMenuLink {
  cursor: pointer; /* not necessary for Bootstrap */
  color: white /* change if you want */
}

<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.2.1/css/bootstrap.min.css" integrity="sha384-GJzZqFGwb1QTTN6wy59ffF1BuGJpLSa9DkKMp0DgiMDm4iYMj70gZWKYbI706tWS" crossorigin="anonymous">

<div class="dropdown">
  <a class="btn btn-secondary dropdown-toggle" role="button" id="dropdownMenuLink" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
    Dropdown link
  </a>

  <div class="dropdown-menu" aria-labelledby="dropdownMenuLink">
    <a class="dropdown-item" href="#">Action</a>
    <a class="dropdown-item" href="#">Another action</a>
    <a class="dropdown-item" href="#">Something else here</a>
  </div>
</div>

<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/js/bootstrap.bundle.min.js" integrity="sha384-3ziFidFTgxJXHMDttyPJKDuTlmxJlwbSkojudK/CkRqKDOmeSbN6KLrGdrBQnT2n" crossorigin="anonymous"></script>