Several options are missing under Plesk > Tools & Settings after upgrade to Plesk Obsidian: Applications & Databases options and General Settings options (DNS Template, FTP Settings and File Sharing)
Restricted mode of the interface is enabled restricting such options.
Connect to the server via SSH
Disable Simple view with the following command:
# plesk bin poweruser --off -simple false
- Obsidian documentation: Plesk in Restricted Mode
- Onyx documentation: Customizing Power User View