The standard major Internet browsers are supported by AIM in Classic - this includes Google Chrome (latest version), Mozilla Firefox (latest version), Apple Safari 10.x and 11.x, MS Edge and IE 11. You may use other unsupported browsers, but this will typically result in a number of errors.
AIM in Lightning is more limited with Internet Explorer. Please note that Salesforce support for IE11 is ending on December 16, 2017. To continue use of IE11 with Lightning Experience, you need to opt-in on the Session Settings setup page and enable Extended Support. To complete the opt-in, you’ll have to read and agree to the terms associated with it. Please see this article written by Salesforce for more details.
Our recommended browsers are either Google Chrome or Mozilla Firefox. These browsers perform the best in terms of speed, display, and errors experienced. We also recommend that you stay up-to-date with all new releases for whichever browser you choose to use.