Uib Dropdown With Empty Name/Lable not Opening

In my application there can me multiple dropdowns with empty name (meaning they do not have a value set to them).

But uib-dropdown does not open when it has empty name/lable.

What can I do?

 <div>
    <span uib-dropdown on-toggle="toggled(open)">
      <a href id="simple-dropdown" uib-dropdown-toggle>
      </a>
      <ul class="dropdown-menu" uib-dropdown-menu aria-labelledby="simple-dropdown">
        <li ng-repeat="choice in items">
          <a href>{{choice}}</a>
        </li>
      </ul>
    </span>
 </div>

Plunker

Answer

Just Adding &nbsp works

<div>
    <span uib-dropdown on-toggle="toggled(open)">
      <a href id="simple-dropdown" uib-dropdown-toggle>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
      </a>
      <ul class="dropdown-menu" uib-dropdown-menu aria-labelledby="simple-dropdown">
        <li ng-repeat="choice in items">
          <a href>{{choice}}</a>
        </li>
      </ul>
    </span>
 </div>

plunker