Problems decrypting credentials on Node-Red 4.0.2

I upgraded my Node-Red installation from 3.1.10 to 4.0.2. I also copied in a project created in 3.1.10 to the projects folder and asked NR to open it. After loading the project, NR displayed this message

setup credentials

When I click on the Setup credentials button, the dialog alert disappears, but nothing else happens. When I go to Projects -> Project Settings the expected dialog window does not pop up. It doesn't do anything.

If I downgrade back to v3.1.10 I can access the project settings dialog just fine and can enter in the passphrase to decrypt credentials. Upgrading to 4.0.2 at that point works just fine, I just still can't access Project Settings.

Weirdly, somewhere in this process, many of my flows' link in and link out nodes lost their connections to each other. I don't know if this is related or due to something else.

Are these bugs, or am I doing something wrong?

Thanks!