Hi Rwil,
I think that the behavior you are seeing is simply a characteristic of HTML. To quote the document linked below, you can't use tabs in HTML "because HTML is a language for expressing content, not formatting." There are several workaround, however. One of the easiest is to use several non-breaking spaces ( ) to create the indentation. You also can use preformatted text with the <pre> tag.
I hope this helps! Please post if you have any further questions.
Megan B.
National Instruments