The Persistent Memory State
macOS features a deeply integrated “Resume” function designed to make your workflow seamless. When you quit an application like Safari or Preview, the operating system quietly takes a snapshot of exactly where you were—which windows were open, scroll positions, and unsaved text—and saves it to a hidden folder called “Saved Application State.” When you relaunch the app, it instantly restores that exact state. While convenient for some, this behaviour is highly frustrating if you prefer applications to open with a completely fresh, blank slate every single time, or if a corrupted saved state is causing an application to repeatedly crash upon launch.
Enforcing a Clean Slate
You can instruct macOS to stop saving these state snapshots globally, forcing all applications to open cleanly. You do not need to use the Terminal for this; Apple includes a specific toggle deep within the System Settings.
Open the System Settings application from your Apple menu. In the left-hand sidebar, navigate to Desktop & Dock. Scroll down the main pane until you locate the section titled “Windows & Apps.” Look carefully for a toggle switch labelled Close windows when quitting an application. By default, this is turned off (meaning macOS keeps the windows saved in memory). Click the toggle to turn it On. From this point forward, when you press Command+Q to quit any application, macOS will permanently discard its current state. The next time you open it, you will be greeted with the default startup window.