Look at the first two lines of the javascript of this otherwise very nifty contribution:

var enablepersist="on" //Enable saving state of content structure using session cookies? (on/off)
var collapseprevious="yes" //Collapse previously open content when opening present? (yes/no)

You will find out that in the current Version 1.0 these variables don't work.

To make it work properly, download and install this.

Full package, including simple instructions to upgrade from earlier install.

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