At one point or another, many have likely been guilty of either downloading way too many extensions or toolbars, downloading one and then forgetting about it, or pointing our device to a site or program we probably shouldn't have and ending up with extensions and toolbars we didn't ask for decorating our browser windows. An update to Chrome on the stable channel, rolled out overnight, looks to help users not only rein in those behaviors, but rein in the Chrome extensions putting a drain on their system resources as a result. The update gives extensions the boot from their hiding place inside your Chrome window's address bar, the omnibox, and shoves them over to the right, on the toolbar. Since only the desktop version of Chrome has a toolbar, of course, that's the only version affected.
The change came through along with the Chrome 49 update, bringing a few other changes with it. Essentially, extensions would be hidden away in the address bar until active, although some hid while active. This meant that, unless users wanted to dive into chrome://extensions and have a look around, they didn't have the fullest picture of what extensions they had. With this new change, a user can see all of the extensions they currently have present in the browser, active or inactive. This allows users to see when they've wound up with too many extensions, unwanted extensions or extensions they don't use often anymore.
The change may not have gotten a good reception from users who have and use a lot of extensions and know which ones they have, or users who just don't want their sidebar cluttered up. For these users, a simple right-click on each extension and then a click on the option to "Hide in Chrome menu" will solve the problem, putting the extension in question into Chrome's hamburger menu located on the far right. Unfortunately, there is no way to disable the UI change and each extension has to be hidden individually. The change rolled out overnight, as stated above, so you should be able to see your extensions next to your omnibox right now. For those interested, head through the source link for the full text from the Chromium team regarding the change and other changes to the UI.