It's important to realize that jsPanel v4 is not a jQuery plugin anymore and also doesn't depend on jQuery anymore. This for example means that you cannot use jQuery methods the way you might be used to from previous jsPanel versions.
The following polyfills are included:
The use of jsPanel is not limited to normal panels. Via plugins jsPanel can also be used as:
The global object
jsPanel provides a few convenience methods that might be helpful, not only for jsPanel.
A fair amount of ...
... allow you to work with already existing jsPanels.
Configurable interactions to drag and resize existing panels are built-in.
Save and restore layout of jsPanels via extension.