When updating forum permissions and selecting more than 6 forums for updating there are 2 things happening on the permissions page:
1. If I use the "Apply all permissions" button the page posts back and nothing happens.
2. If I use the "Apply permissions" button for a specific forum I selected I get "The submitted form was invalid. Try submitting again."
Page seems to work fine and saves when selecting 6 or less forums. This is a bit of a problem because there is also the "All forums" checkbox when selecting the forums.