Why is the Disney Plus display blank/black out after login?

Welcome Sordor,

Thank you for using Apple Support Communities. Based on your post, you're having issues signing in to Disney+ on your Mac. We'll do our best to assist with this.

Are you trying to sign in to Disney+ using Safari or another browser?

If you've had issues signing in, try out steps in: Login issues with Disney+

If you're using Safari, you can test signing in using another browser.

Should the issue be isolated to Safari, we'd recommend clearing the history and test it out again: Clear your browsing history in Safari on Mac

For log in issues for Disney+, we'd recommend speaking with their support team: Disney+ Help Center

In case you continue to have other issues, please reply back with additional details and we'll do our best to help out.

Wishing you well, take care.