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Changes between Initial Version and Version 1 of Ticket #28709, comment 1

initial	v1
1	1	I'm also creating controls and sections in the Menu Customizer, so this would be a big help. Should also be able to use it internally for #28580.
2	2
3		While the contents of panels should be loaded as-needed, I don't think it makes sense to be creating panels dynamically, internally or externally. That being said, some sort of structure is needed to assign sections to panels, so having a panel model makes sense. I'd also be okay with moving the section and panel expanding/collapsing functionalities from `accordion.js` to something more structured and customizer-specific.
	3	I'd be okay with moving the section and panel expanding/collapsing functionalities from `accordion.js` to something more structured and customizer-specific.