I'm trying to get a page's content dynamically so I can open in a modal. What's the best way of getting the html from a page given an ID/page url?
I like the suggestion which is provided by @jammykam. To fit to your requirements I would create a new device and there you can create your own layout for that specific modal.
You can create your device under
Then you can access to the device related rendering defintion through the following url: http://[url]?sc_device=modal