If you’re using the HTML training material type and really want to get rid of that instantaneous pop-over saying the activity is completed, here’s some CSS code to hide it:
/*Hide pop-over completion message for HTML content*/
div.intime-completed.ng-star-inserted > div {
display: none !important;
}
The activity will still be marked completed everywhere it needs to be. This just prevents the pop-over message from displaying.