Empty screen when setting up WPML for the first time

Overview of the issue

When setting up WPML for the first time, the first step of the setup wizard asks you to choose your site languages. If you add just one language, then remove it, you can proceed to the second step of the wizard without adding any languages. This leads to an empty screen and an error in your browser console:

TypeError: Cannot read properties of undefined (reading ‘english_name’)
at bi (app.js?ver=4.5.1:111)
at Yo (app.js?ver=4.5.1:57)
at gl (app.js?ver=4.5.1:57)
at us (app.js?ver=4.5.1:57)
at ls (app.js?ver=4.5.1:57)
at Ql (app.js?ver=4.5.1:57)
at Yl (app.js?ver=4.5.1:57)
at Ls (app.js?ver=4.5.1:57)
at app.js?ver=4.5.1:57
at ts (app.js?ver=4.5.1:57)

Workaround

Make a full backup of your site before proceeding.

1. Access your website database.
2. Open your wp_options table. It might have a different prefix than wp_ depending on your site configuration.
3. Search for WPML(setup) key and delete that row.