I'm trying to build admin navigation link for my addon, and having hard time figuring out what's really does these options signify:- Use class to build link: Always | Only when data is provided | Never. I see that some of the options have 'Never' while others have 'Only when data is provided'. Questions: 1. Which 'class' is this option talking about? 2. What decides 'Always' , 'Only when...' and 'Never'? Thank you for reading and I'd really appreciate every response.