A California health insurance company’s Web site was flagged by security products as serving malicious content. The malicious link was injected by a browser extension installed on the computer of a Blue Shield employee. The extension in question was Page Ruler, a Chrome addition with some 400,000 downloads. It’s not uncommon for extension makers to sell or lease their user base to shady advertising firms, or in some cases abandon them to cybercriminals. A simple Internet search shows this same javascript code is present on hundreds of other Web sites.”]
Source: https://krebsonsecurity.com/2020/03/the-case-for-limiting-your-browser-extensions/