Mark Zuckerberg wants to unify the company's separate messaging services. Not everyone agrees, especially considering the privacy nightmare it could lead to. The social networking giant, however, could be attacking the problem from a slightly different angle. There are now signs that Instagram is playing around with a version of its Direct messaging feature for web browsers on desktops. And while this might sound like a great standalone feature, it could also be just the opening salvo for a series of changes.