Trying to set up OAuth in application, and getting errors on the auth code exchange for access token. Tried the exact same request in Postman and getting 200s. My request url, headers, and body looks good and identical to the one I am sending through Postman...
Error Setting Up Request to Docusign

Best answer by JohnSantos
The error message you're encountering, "Failed to execute 'open' on 'XMLHttpRequest': Invalid URL," suggests that there is an issue with the URL being used to retrieve the DocuSign access token. This could be due to several reasons, such as an incorrectly formatted URL, an empty URL, or an issue with how the URL is being constructed in your code.
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