I was following the instructions for configuring Sentry for error monitoring, but when I restarted the server I kept getting "ValueError: Invalid Sentry DSN" in my logs and the server refused to start.
It turns out that in the Client Keys section of my Sentry project, I need to hit the "Show deprecated DSN" link in order to show the DSN that includes the secret. Apparently newer Sentry clients no longer require having the secret in the URL, which is why Sentry lists it as deprecated.
It would be useful to specify in the instructions that the deprecated DSN is required in order to avoid confusion.