How well does jQuery support backward compatibility?

Question

We have had issues with Mootools not being very backward compatible specifically in the area of drag and drop functionality. I was wondering if anyone has had any similar pr

Answer 1

In my experience, jQuery 1.x has been very backwards-compatible until version 1.9.

The jQuery 1.x line had major changes as of jQuery 1.9.0. We strongly recommend that you also use the jQuery Migrate plugin if you are upgrading from pre-1.9 versions of jQuery or need to use plugins that haven't yet been updated. Read the jQuery 1.9 Upgrade Guide and the jQuery 1.9 release blog post for more information.

And don't upgrade to 2.0 until you're sure that this isn't an issue for you:

jQuery 2.x has the same API as jQuery 1.x, but does not support Internet Explorer 6, 7, or 8.