With the release of Chrome 69, Google has decided to strip the “www” and “m” subdomains from the URL displayed in Chrome’s address bar. For example, when a user visits www.bleepingcomputer.com, the www would be stripped and displayed.
When this was discovered, users and security experts expressed concerns that this new behavior will cause confusion for users who may think that they are going to a particular site, but may actually be going to a completely different one.
As stated by a Chromium developer in the behavior’s bug report, the www and m (for mobile) subdomains are being classified by Google as “trivial” subdomains because they feel most people do not need to be concerned with the information they represent.
The article includes directions about how Chrome users can “stop the stripping of trivial subdomains.”