Changing the markup into:
<span style="display: inline-block">
<button id="possible-actions">Action</button>
</span>
<ul style="display: none">
<li><a href="#">Reopen</a></li>
<li><a href="#">Close</a></li>
<li><a href="#">Delete</a></li>
<li><a href="#">Move...</a></li>
</ul>
Fixed the issue. The styles I use are:
- display: inline-block - because I need to control some width/height dimmentions
- display: none - because I create & show menu on demand when button is clicked