Wait, it seems I did not get you and I am now really confused.
In your first message when you said that “the sequence of
javascript library loading has changed”, were you referring to the
JavaScript engine?
I mean, were you talking of the interpreter or however is called
in WebKit, the thing that executes the JavaScript?
Or maybe you were talking about the jQuery library?
In any case, this whole issue seems to be an old bug in jQuery or WebKit
(
see here), but it somehow was not affecting calibre before.