"will no longer be supporting" is completely fine, though.

It's also more consistent with "no longer", which implies a progressive action. An alternative is "will not support", which is no longer indicating (or does not indicate) that it had been supporting epub for a while.

That said, "will no longer support" is more succinct and clear enough.

> This is answered in the next sentence of the article: it’s “support” not “be supporting,” Microsoft.

That's not an answer to "What's wrong with this?", that's the author's preferred wording.

Both the future and simple versions are appropriate, whereas the author makes it a point to highlight their preference.

And of course here we are, poking it further.

“Microsoft Edge will no longer be support e-books that use the .epub file extension” sounds very wrong.

“support”, as the author of the article suggests, should replace “be supporting”, not just “supporting”. The simple future is called for, not the future continuous.

You misread the suggestion.

Will no longer support