openmct/platform/commonUI/general/res/templates/progress-bar.html

<span class="l-progress-bar s-progress-bar"
      ng-class="{ indeterminate:ngModel.unknownProgress }">
    <span class="progress-amt-holder">
        <span class="progress-amt" style="width: {{ngModel.progress}}%"></span>
    </span>
</span>
<div class="progress-info hint" ng-hide="ngModel.progressText === undefined">
    <span class="progress-amt-text" ng-show="ngModel.progress > 0">{{ngModel.progress}}% complete. </span>
    {{ngModel.progressText}}
</div>