A window can remain positioned for a disconnected monitor. macOS window commands, display arrangement and temporarily changing resolution can bring it back without deleting app preferences. Use Mission Control and the Window menu to confirm the app is open with a window.
Differential
Likely causes of “Mac app window opens off screen”, and how to tell them apart
- 1
The window remembers a position on a display that is no longer connected
What separates it The app is open in Mission Control or the Dock, but no window is visible, after using an external display.
How to confirm Use Mission Control and the Window menu to confirm the app is open with a window.
- 2
The display arrangement has changed
What separates it The window sits outside the current desktop area after changing resolution or the display arrangement.
How to confirm Reconnect the former display, or temporarily mirror the displays.
- 3
The window is minimized or in another Space
What separates it The window is not off screen but in a different desktop Space or minimized to the Dock.
How to confirm Check Mission Control and the Dock for the window.
- 4
A saved app preference holds the bad position
What separates it The window opens off screen every time the app starts.
How to confirm Move the window and quit and reopen the app with only the intended displays connected.
Before you touch a setting
Record this first — changing settings destroys the evidence
- Whether the app appears in Mission Control and the Window menu.
- The displays that are connected now and were connected before.
- Whether it happens with one app or with many.
Try in this order
0 of 4 completedCapture the exact symptom
ReversibleUse Mission Control and the Window menu to confirm the app is open but its window is outside visible displays.
Run the smallest isolation test
ReversibleReconnect the former display if available, use Zoom/Move commands, or temporarily mirror/change resolution.
Correct only the proven cause
ReversibleMove the recovered window to the main display before returning the original arrangement.
Verify before changing anything else
ReversibleQuit and reopen the app with only the intended displays connected.
Stop boundary
When this stops being a self-service repair
- !Avoid deleting the app's preferences until the window commands and display changes have been tried.
Evidence ledger
Sources behind this answer
Exact questions
Common questions
How do I get a window back that is off screen on a Mac?+
Use the Window menu's Zoom or Move options, reconnect the earlier display, or mirror the displays temporarily to bring the window back into view.
Why does a window open off screen?+
A saved position may sit on a display that is no longer connected.
How do I recover it?+
Use Window menu options such as Zoom or Move to bring it back.
Can I reset it?+
Try resetting the app or restarting.