Chrome will shortly start warning users if they download a software installer that could "harm their browsing experience".
The Google browser already blocks malware-ridden websites and warns about malicious downloads via its Safe Browsing service. Now it will also alert users if their download includes unwanted software or messes with their browser settings.
For example, a download might get flagged if it tries to add a new search bar to your browser, switch your default homepage, or install unwanted additional software.
"We’ll show a warning in Chrome whenever an attempt is made to trick you into downloading and installing such software," said Moheeb Abu Rajab, staff engineer with Google Security in a blog post.
"If you still wish to proceed despite the warning, you can access it from your Downloads list."
The warning will be shown at the bottom of the browser, where other download notifications appear, saying the file has been blocked because it "may harm your browsing experience".
The Safe Browsing system is being made available to other browsers too, so it could find its way into Mozilla's Firefox as well.
Because Firefox is free, it's often offered by dodgy download sites. Search for the browser, and unofficial sources will pop up in the results - or in ads, which are, of course, bought from Google.
Less web savvy individuals might not realise that such sites aren't official, and will download the browser via them. They'll get the browser, but as Mozilla has pointed out, they may find themselves stuck with unwanted settings or dodgy toolbars.
"We are happy to see that Google is continuing to improve its detection of potentially unwanted software, especially since Firefox relies on Google Safe Browsing to block malicious downloads," a Mozilla spokesperson told The Register, saying it was "investigating implementing this new extension" and hoped it "reduces unofficial rebundled software that targets Firefox and other well-known publishers through Google search ads".
This article originally appeared at pcpro.co.uk