I was attempting to work on an old(ish) project that uses the Trello API. Running the same code in a local server like when I initially developed the project now no longer works.
When I attempt to authenticate with Trello, the initial authorization dialog appears as expected, and upon accepting, the dialog redirects to https://trello.com/1/token/approve, but it hangs on a blank white page, and the authentication flow never completes. I am running the identical code from when I initially developed the app, which is the code currently running as expected on my website.
I tried using the same API key as the live instance, adding both http://localhost:8080 and http://127.0.0.1:8080 to the list of allowed origins for the key with no luck. I also tried running the local server on port 80 (and adding http://localhost and http://127.0.0.1 to the allowed origins); again, no luck.
I don't think I have worked on this project since they moved API keys from the old app key page to the power-up admin portal; I am not sure whether something changed in that migration I wasn't aware broke local development.