Cannot display island on external monitor when both displays are active (dual-screen mode)

[Freeman211314]

Environment: Apple M5 Pro, Samsung LS27A800U 4K (main display), macOS built-in Retina XDR
▎
▎ Issue: In dual-screen mode, the island only appears on the MacBook built-in display. The Display settings dropdown only shows "Built-in
▎ Retina Display" and cannot select the external monitor. The island only shows on the external display when the MacBook lid is closed
▎ (clamshell mode).
▎
▎ Expected: Allow selecting the external monitor as the target display even when both screens are active.

[wxtsky]

Thanks for the detailed report. The display dropdown is populated directly from NSScreen.screens with no filtering, so "only Built-in shows up" means macOS is reporting just one screen to the app at that moment, rather than CodeIsland dropping the external one.

Could you check a few things:

1. Is the external Samsung in extended mode (not mirrored)? Mirrored setups can present as a single logical screen.
2. Grant CodeIsland Screen Recording permission (System Settings → Privacy & Security), then relaunch — it affects how the app can enumerate/identify displays.
3. Does the dropdown pick up the external display if you open Settings after both displays are active, or after toggling the arrangement in System Settings → Displays?

If it still only lists Built-in, please share: macOS version, how the monitor is connected (HDMI / USB-C / dock), and whether it's set as the primary display. That'll help me tell whether it's an enumeration timing issue we can work around in code. Keeping this open to track (and #185 was merged into this one).