UPDATE 08/05/2016:

After looking into the issue closer, it turns out that the .serialize() method is no longer serializing the values of any disabled objects or their children.  This is a breaking change, as it is common practice to disable a page, or portion of a page, during a post to prevent additional clicks/selections/whatever.  I don't see anything in the notes that this was intended, but that is the current functionality.  Is this new functionality intended?  If so, is there a way to serialize these values?

ORIGINAL POST:

We upgraded from 2.2.0 to 3.1.0 last week, and have run into a selector issue.  It appears that a selector that contains an ID, no longer works correctly.  For example:

$('#operatorForm input[type="hidden"]').serialize()

no longer works.  If I change '#operatorForm' to 'form' it works, but nothing is returned if I use an #ID selector.  We are noticing very strange behavior throughout our entire site when using IE or Chrome (latest versions), but Firefox works.  Unfortunately, Firefox is not a requirement, but IE and Chrome are.

Is this a known issue?