Error when authorising the site with FA

Problem/Motivation

When authorising the site against FreeAgent, I got as far as logging into FreeAgent, entering my 2FA and then when returned to the site I got "The website encountered an expected error" message.

In the logs, I found this error

LogicException: The controller result claims to be providing relevant cache metadata, but leaked metadata was detected. Please ensure you are not rendering content too early. Returned object class: Drupal\Core\Routing\TrustedRedirectResponse. in Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext() (line 154 of /app/web/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php).

Steps to reproduce

1. Fill in client id and secret
2. Click authorise
3. Fill in credentials and authorise the app