­ support has been around for at least a decade and it can be done server side with any logic.

It's probably not needed today but when I first used it the logic was along the lines of adding it at the 5th 7th 9th characters provided there were at least 4 more characters after each ­ or some such while being wary of hanging the last word etc.

It's a soft hyphen meaning the browser will break if needed otherwise ignore it. It's an HTML feature rather than a CSS one which also has implications.