Confirm that the Dock is the item staying visible
The Dock contains app shortcuts and usually Trash at a screen edge. The top menu bar and an app’s own toolbar are different. If the issue only concerns the top of the screen, follow the menu bar guide instead of changing Dock behavior.
Enable and test automatic hiding
Automatic hiding should leave the Dock out of view until you move the pointer to its screen edge. Test it with a normal app window before investigating more complex display arrangements.
- Open Apple menu > System Settings > Desktop & Dock.
- Enable Automatically hide and show the Dock.
- Move the pointer well away from the Dock edge and dismiss any open Dock menu.
- Move back to its edge to confirm that the Dock can appear again.
Source: Apple: Desktop & Dock settings ↗
Check the interaction that keeps it visible
An open Dock context menu or the pointer resting at its activation edge can make a visibility test misleading. Finish the menu interaction, move the pointer and compare again. If the behavior only occurs while using one app, save your work and check whether that app is requesting attention before changing system-wide settings.
Separate Dock size, hiding and full-screen behavior
A smaller Dock is still visible unless automatic hiding is enabled. Maximizing a window is also not the same as using macOS full screen. Check the setting directly rather than using a wallpaper preview as evidence of how your working windows should behave.
| What you changed | What it controls |
|---|---|
| Dock size | How large the icons are. |
| Automatic hiding | Whether the Dock stays visible when unused. |
| Dock position | The bottom, left or right screen edge. |
| Menu bar automatic hiding | The top bar, independently of the Dock. |
Source: Apple: Desktop & Dock settings ↗
Test displays and apps without resetting preferences
On a multi-monitor setup, test the intended edge on each display and note where the Dock appears. Change one condition at a time. If the issue persists, save documents and try reopening the affected app or restarting the Mac at a convenient time. Avoid deleting preference files as a first step; that can discard a layout you wanted to keep.
Restore an always-visible Dock
Turn automatic hiding off if the extra space is less helpful than predictable app access. Keep the previous size and position if those already work. You do not need to uninstall apps or remove shortcuts to restore normal Dock visibility.
Source: Apple: Desktop & Dock settings ↗