I've used a few different programs over the years including LibreOffice, but have settled on Pages and Final Draft for my screenplays with final formatting in Pages. A double hard return after a paragraph does a great job with putting in white space. As far as the other tags go, most of those are saved for special occasions or when I'm formatting a screenplay to look like a screenplay.
What browser/OS you using? That might have a part to play in it.