I’m using an accordion element on a few pages on my site and it has defaulted to “open” and doesn’t seem to collapse. I’m only noticing this since updating to X-theme 4.6.0.
See here:
http://medicine.st-andrews.ac.uk/bequests/
And here:
http://medicine.st-andrews.ac.uk/teaching/bsc-hons-medicine/gateway-to-medicine/