http://127.0.0.1:8888 on that laptop I cant connect
yes, the address is only live for a few seconds during the actual authentication sequence. (if the app actually enables the callback reception)
otherwise it opens a browser and puts the url and data in the address field, for the user to manually copy the data (usually an access token)
So I was able to get to the page where it says the project needs to be authenticated and to login to spotify. when I do that, I get the invalid client id error. I tried both using the SSH method and via the chromium browser on the pi.
Looked on the developer forum and didnt really see anything to help.

