
For accounts with activated Lock Profile feature, when strangers view, they will only see very limited information, a small part in the 'About' section. Additionally, locked profiles will display an additional small green icon with a lock image inside. Activating the lock also means converting all previously 'Public' posts to 'Friends Only'. If the viewer is already friends with the safely locked account, they can still see normal contents, images, stories, etc.
To safely activate the lock, Facebook users in Ukraine can open the Facebook app, go to their personal profile page, tap More (the ... symbol below the avatar), choose Lock profile, and confirm.Source