If there's one feature defining Golden Gate's rough edges, it's Mission Control. A post in r/MacOS calling it chaos drew hundreds of upvotes in launch week, alongside a steady stream of smaller threads: shortcuts that do nothing, App Exposé missing minimized windows, apps that won't stay assigned to a desktop, full-screen apps misbehaving across displays.

Some of this is macOS. Some of it is third-party tools. Some of it is settings you forgot existed. This guide walks through them in the order that finds the cause fastest.

Step 1: Find out which layer is broken

Before changing anything, test Mission Control three ways:

  1. Trackpad: swipe up with three fingers (or four, depending on your settings).
  2. Keyboard: press Control-Up Arrow, or the Mission Control key.
  3. Your usual method: a mouse button, a hot corner, or a utility.

If trackpad and keyboard work but your mouse button doesn't, the problem is your mouse utility, not macOS. Jump to Step 5.

If nothing works, or Mission Control opens but behaves strangely, it's macOS or its settings. Continue with Step 2.

Step 2: Restart the Dock

Mission Control, Spaces, App Exposé, and the Dock are all run by the same process. When Mission Control gets stuck, restarting it often clears the problem without a full restart. 

killall Dock

The Dock disappears for a second and relaunches. Your windows and apps aren't affected. If Mission Control works again, you've found a glitch rather than a setting problem; note what you were doing before it broke so you can report it.

Step 3: Check the settings that change how Spaces behave

Open System Settings > Desktop & Dock and scroll to the Mission Control section. Several options quietly change what Mission Control shows and where windows go:

  • Automatically rearrange Spaces based on most recent use. When on, desktops reorder themselves as you switch. If your desktops seem to shuffle randomly, turn this off. For most people, this alone fixes "chaos."
  • When switching to an application, switch to a Space with open windows for the application. Causes sudden jumps between desktops when you Command-Tab.
  • Group windows by application. Changes whether Mission Control shows windows individually or clustered by app.
  • Displays have separate Spaces. Controls whether each monitor has its own set of desktops. Changing this requires logging out, and full-screen behavior across monitors depends heavily on it.

Upgrades don't usually change these, but it's worth confirming they match how you work, especially before assuming a bug.

Step 4: Reassign keyboard shortcuts and gestures

Shortcuts that look correct can still stop responding after an upgrade.

  1. Open System Settings > Keyboard > Keyboard Shortcuts and select Mission Control.
  2. For each shortcut you use (Mission Control, Application windows, Show Desktop, Move left or right a space), click the shortcut and press the key combination again, even if it's already set.
  3. Make sure the switch next to each one is on.

Then check gestures in System Settings > Trackpad > More Gestures: Mission Control, App Exposé, and Swipe between full-screen applications.

If a shortcut still doesn't work, look for conflicts. Apps like window managers, launchers, and screenshot tools often claim the same key combinations.

Step 5: Fix mouse and gesture utilities

Many mouse utilities trigger Mission Control and Spaces by simulating trackpad gestures. They did that by writing undocumented data into system input events, and macOS 27 stopped reading it. As a result, mouse buttons mapped to Mission Control, Spaces, Show Desktop, or App Exposé stopped working, while normal clicks and scrolling kept working.

  • Mac Mouse Fix: the developers have fixed it in their source code, and published a temporary build for affected users until the next official release. Check the project's GitHub page.
  • Other mouse, trackpad, and gesture utilities: check each developer's website or issue tracker for a macOS 27 update.
  • Workaround while you wait: remap the mouse button to a keyboard shortcut (for example Control-Up Arrow) instead of a gesture action, if your utility supports sending keystrokes.

Step 6: App Exposé doesn't show minimized windows

Users report App Exposé no longer lists an app's minimized windows at the bottom.

Workarounds until it's fixed:

  • Press Command-Tab, move to the app, then hold Option before releasing Command to restore its minimized windows.
  • Right-click the app in the Dock to see its open windows, including minimized ones, and choose one.
  • Turn on Minimize windows into application icon in Desktop & Dock if you prefer minimized windows to live with their app rather than at the right of the Dock.

Step 7: Apps won't stay on their assigned desktop

If you right-click an app in the Dock and choose Options > Assign To > a specific desktop, but windows open elsewhere:

  1. Reassign the app: set it to None, then back to the desktop you want.
  2. Check that Automatically rearrange Spaces is off, or your desktop numbers keep changing.
  3. For apps restored from a previous session, quit and reopen them once after reassigning.

Step 8: Full-screen apps and multiple displays

Reports include full-screen apps moving to the wrong display or refusing to move between displays.

  • Check Displays have separate Spaces (Step 3). Full-screen apps behave very differently depending on this setting.
  • Exit full screen, move the window, then re-enter full screen on the display you want.
  • Use Split View and tiling alternatives: the green window button's tiling options can often replace full screen for side-by-side work, without creating a separate Space.

Step 9: Reset Spaces, as a last resort

If Mission Control is still erratic, you can reset the saved Spaces configuration. This removes extra desktops you've created and their app assignments, but doesn't touch your files or apps. 

defaults delete com.apple.spaces
killall Dock

Log out and back in. You'll start with a single desktop; recreate additional desktops in Mission Control and reassign apps.

Report it

Mission Control problems that persist after these steps are likely Golden Gate bugs. Report them in Feedback Assistant with:

  • Your Mac model and whether you use external displays
  • Your Desktop & Dock Mission Control settings
  • Exact steps to reproduce
  • A screen recording

The short version

  • Test trackpad and keyboard first. If only your mouse fails, it's the utility.
  • killall Dock restarts Mission Control safely.
  • Turn off Automatically rearrange Spaces if desktops shuffle.
  • Re-enter shortcuts in Keyboard Shortcuts, even if they look right.
  • Minimized windows missing: Command-Tab, hold Option, release Command.
  • Last resort: reset Spaces with defaults delete com.apple.spaces.