Theme preview not showing

I have Ghost 5.

When I click on Site Design I assume I’m supposed to see a preview of my site. I don’t, it’s just blank.

When I select a new theme, it says it’s active. But when I go to my domain in a browser, it shows the default theme.

I don’t know if the two things are related, but something is wrong.

Do you run a proxy? Try turning it off if so. Also check your co sole log with dev tools- might have a CORS error?

I’m using Bitnami to deploy Ghost on AWS Lightsail

I don’t know enough about that setup to be able to point at the problem, but if you open your console log in dev tools (f12 on some browsers), what do you see?