All the code examples on this page are doubling any brackets ([], {}, ()). How have they managed that? Not a fantastic first impression of its capabilities...
Not only that, but the Golang example is full of errors. Parameter definitions don't have colons between name and type. The map for seen elements is declared as a, but later referenced to as m. The append instruction references uniques, which is undefined. The return statement also references uniques.
I'm going to give them the benefit of the doubt and assume this is a marketing site problem and not a product problem, but either way, not a good look. Reminds me of Google's big Bard announcement including a wrong answer in the image.