Gmail will stop working on Chrome for XP and Vista in 2017

Older versions of Chrome will be ported directly to Gmail's HTML website interface in December

When you update your Chrome browser, you'll see a banner appear at the top of your Gmail interface on February 8, 2017. This banner is a reminder to update your Chrome version for those who still Use version 53 or older to version 55, this is repeated with updates with some major security. This banner will disappear once you have updated to the new version of Chrome - unless you are still using Windows XP or Vista. Google stopped notifying Chrome version updates for customers using version 49, when Microsoft no longer supports these Windows platforms.

So, what happens if users don't or can't update their Chrome version?

Gmail will still work as usual throughout 2017. However, sometime in December, users will be switched to the basic HTML version of the email service and will be vulnerable to security risks. Google says the best thing you can do is upgrade XP or Vista as soon as possible to a more modern version of the operating system.

According to Engadget