In order to remove BrowserWatch Chrome Extension completely you will need to reset Chrome back to its initial settings. This process will erase all configuration information from Chrome such as your home page, tab settings, saved form information, browsing history, and cookies. To reset Internet Explorer, click on the Reset settings button as shown in the image above. Internet Explorer will now erase all your personal data and disable all add-ons and toolbars. All of your bookmarks, though, will be preserved.
Source: https://www.bleepingcomputer.com/virus-removal/remove-browserwatch-chrome-extension