[DiapDealer]

It is my understanding that tab entities (or characters) are still going to be collapsed into a single space by just about any renderer out there. Without some sort of PRE tag, there's very little point in using them.

Even our Sigil Mend code won't preserve tab entities/characters not inside pre tags. They get converted to a single space. Inside of pre tags, a tab entity will be preserved if it's in the preserve entities list, or converted to the U0009 character if it is not.