I've created a Hosted Checkout and filled in the successURL with a valid URL, but after checking out I am not redirected anywhere
Yes that is indeed correct, you will have to enter all three URLs - Failure URL, Success URL and Cancel URL in the redirect URL setup section for the hosted checkout to take effect. Please refer to the below link where we explain setting up hosted checkout feature in more detail.
Turns out you need all three URLs entered before they take effect? started to work after I put in all 3...
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