How can I add a DIV similar to Users->Advanced Options -> Calendar Options?

How can I add/append a DIV similar to Users->Advanced Options → Calendar Options in the Users advanced option section?

The data that will be displayed in that section/div is depending on the user’s info, so it’s not just hardcoded but needs vars, too.

Does it need to be in “/custom/”?
It needs to be upgrade stable.

What is your SuiteCRM version?

Yes, for upgrade-safe you need to add code under /custom/ folder.