To use Concepts in a resizable window with Stage Manager on an external display, you need to enable the Mirror Everything setting.
- With Concepts open, tap the Settings icon in the status bar.
- Choose the Interaction tab.
- In the “External Displays” section, toggle the switch for Mirror Everything to On.
- Restart Concepts for the change to take effect.
Important: We know this setting name is not intuitive when Stage Manager is active. Unfortunately, Apple does not provide a way for an app to detect if Stage Manager is enabled. The setting is named for its function when Stage Manager is disabled.