The Disorienting Desktop
macOS utilizes a virtual desktop system known as Spaces, allowing you to organize your open applications across multiple distinct screens. By default, macOS tries to be “helpful” when you switch applications. If you are working on Desktop 1 and you click the icon for an application (like Safari) that is currently open on Desktop 3, macOS will automatically slide your entire view over to Desktop 3. Furthermore, if you plug in an external monitor, macOS might automatically shuffle your full-screen applications around. For power users who intentionally leave reference material on specific monitors or spaces, this automatic sliding and switching destroys spatial organization and causes severe disorientation.
Disabling Automatic Space Switching
To maintain strict control over your virtual environments and stop macOS from automatically switching spaces when you change applications, you must adjust the core Mission Control settings.
Open System Settings (click the Apple logo in the top-left corner). In the left-hand navigation pane, scroll down and click on Desktop & Dock. Scroll down the main window until you reach the section labeled Mission Control. The very first option in this section is a toggle labeled When switching to an application, switch to a Space with open windows for the application. Click this toggle to switch it to the Off position. While you are here, if you use multiple monitors, ensure the toggle for Displays have separate Spaces is turned On. Now, if you click the Safari icon while on Desktop 1, macOS will not drag you to Desktop 3; instead, it will simply launch a new Safari window on your current desktop, leaving your layout intact.