Accordian Not Working in Internet Explorer

Hi there! Great plugin, it’s been very helpful for me with my latest project!

I only have one issue; I have some spoilers in an accordian, and they seem to be working in chrome and safari, but in IE one automatically opens when the page loads (they should be all closed to begin with) and stays open on top of all the other ones, so that no matter which one I click, the inital one is the only one showing.

I edited the code a little to have the content of the spoiler open to the side instead of below. You can get an idea by checking out the page, renatavanzetto.krsites.com/receitas.

I’m not sure what’s causing this or how to fix it. Any ideas?

https://wordpress.org/plugins/shortcodes-ultimate/