Magento 2.1.18 is the final 2.1.x release. After June 2019, Magento 2.1.x will no longer receive security patches, quality fixes, or documentation updates.
To maintain your site's performance, security, and PCI compliance, upgrade to the latest version of Magento.

Supported browsers

Storefront and Admin:

Internet Explorer 11 or later, Microsoft Edge, latest–1
Firefox latest, latest–1 (any operating system)
Chrome latest, latest–1 (any operating system)
Safari latest, latest–1 (Mac OS only)
Safari Mobile for iPad 2, iPad Mini, iPad with Retina Display (iOS 7 or later), for desktop storefront
Safari Mobile for iPhone 4 or later; iOS 7 or later, for mobile storefront
Chrome for mobile latest–1 (Android 4 or later) for mobile storefront

Here, latest–1 means one major version earlier than the latest released version.

Sep 6th, 2018