I'm sure you're aware of this, but for others who may not know: the 2.x versions of jQuery dropped support for old browsers (IE 6, 7, 8) to reduce size (12% smaller) and complexity necessitated by being so backwards-compatible [0].

Thankfully we only support IE9+ where I work, so I grab the latest 2.x version these days.

[0] - http://blog.jquery.com/2013/04/18/jquery-2-0-released/