I can't find a way to get the list of opens to expand so it's more than 13 names long before you have to scroll. With 1300 opens, that's 100 screenshots taken one at a time. BUT the free version of ChatGPT doesn't 'see' so even if you do make 100 screenshots, it won't turn them into data for a spreadsheet unless you pay. Pay for Squarespace to send emails, then pay for ChatGPT, then spend hours screenshooting...
Stupidly, I paid annually for Squarespace email, not monthly. And it's not refundable. The funniest part of all this are the videos Squarespace makes, touting their amazing in-depth analytics. What a joke!!