Permissions checkboxes have disappeared on the Admin page for administrator users All of the checkboxes on the Permissions page (/admin/people/permissions) have disappeared.

I see the permissions for a split second as the page loads before they disappear, so I think this is a Javascript or CSS issue.

Also, if I edit a single role's permissions (i.e., /admin/people/permissions/3), the checkboxes are there. This only happens when using the main permissions page. 

Example of the disappearing checkboxes:



What I've done


I've switched my theme and admin theme to Stark to make sure my theme wasn't hiding the permissions.
I was using the jQuery Multi module to upgrade jQueryUI for some custom scripts, so I disabled that.
I've searched if anyone else has had this issue, and the only thing I've found is https://drupal.org/node/1649186. I'm not familiar with Organic Groups, and I haven't renamed any machine names, so that post didn't get me very far.
Oh my, I just discovered what it is and I feel really ridiculous... I'm using the admin menu module, and in the configuration, under "System tweaks", there is an option "Collapse module groups on the Permissions page". It is checked. The checkboxes weren't hidden after all. The groups were just collapsed... Maybe I just need a break and another cup of tea.