This is the same glitch that many abused to get 5x Grapes of Wraith and such, this glitch was amazing. I've used it plenty of times to grab many cove items.
Here's how it's done;
1. Visit the Smuggler's Cove page on Internet Explorer (Already have sufficient amount of dubloons on hand).
2. Change the browser to Offline-Mode.
3. Refresh at the cove every XX:XX:01 NST.
You won't get cove banned because your in offline mode, however if a change were to occur on the page (a new cove item appearing) it will update and pop-up, and you can buy it!
Happy Cove-Hunting!
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