Since this is about restrictions: Is it allowed to have localhost as a redirect uri?
This comment and the responses on the documentation page certainly suggest so: Web API Authentication - #4 by rvfx
Yet when i try it, i get the error
The 'redirect_uri' parameter does not match any of the OAuth 2.0 Client's pre-registered redirect urls.
The localhost url is present in the Web interface settings, even after reloading the page.
Other urls work just fine, but its a pain to update the dev server every time i want to test new code.