Reduced old IE support: jQuery UI 1.11 officially dropped support for IE7 but left all the existing workarounds in place. jQuery UI 1.12 has removed all of the IE7 workarounds. In addition, official support for IE8, IE9, and IE10 have been removed, but the workarounds are still in place and will be removed in 1.13. This coincides with Microsoft’s end of regular (non-extended) support for these browsers which occurred in January.