After closing modal, gray background not disappear! You can check it on Group page. You must create group first, then click "Add participant" and close. You`ll see it. About modals on documentation you can find at materializecss.com. Today I create "Leave/delete group" button with the same modal, and I still face with this bug. Help me please
Due to limitation, I can post just 2 links. Ask if something is not clear
You can use jQuery to hide it when its supposed to hide.
Also, for closing modals the code is