macOS reset app window to default size and position

Maybe it’s because I’m a bit of a perfectionist, but I sometimes like to reset an app’s window to its default size and position. It looks like I’m definitely not the only one.

The summary of the above links is that the window information is usually stored in ~/Library/Preferences or ~/Library/Saved Application State, and you can get away with removing the matching application preferences files in one of those locations, or carefully editing it to remove just the window position if that’s what you want.

This is generally true, but not all the time (as shown in the case of the Mail app).

This means this solution isn’t perfect. Did I say I was a perfectionist?

Finding every window position preferences

From the files we could find from the earlier solution, we can see that the window position is either in a NSWindowFrame key, or a key that starts with NSWindow Frame, e.g. for Activity Monitor and Finder:

$ plutil -p ~/Library/Preferences/com.apple.ActivityMonitor.plist | grep NSWindow | grep Frame
  "NSWindow Frame main window" => "161 208 960 640 0 0 1728 1079 "

$ plutil -p ~/Library/Saved\ Application\ State/com.apple.finder.savedState/windows.plist | grep NSWindow | grep Frame
    "NSWindowCloseButtonFrame" => "{{19, 876}, {14, 16}}"
    "NSWindowFrame" => "42 1193 1652 910 -87 1117 1920 1055 "
    "NSWindowMiniaturizeButtonFrame" => "{{39, 876}, {14, 16}}"
    "NSWindowZoomButtonFrame" => "{{59, 876}, {14, 16}}"

Moreover, this setting is always stored in a plist file, the property list file that macOS apps store their preferences in.

So we can try and find for those keys in all plist files in the whole ~/Library!

find ~/Library -type f -name '*.plist' -exec grep -E 'NSWindow ?Frame' {} +

Thanks to that, we uncover more locations! Here’s the exhaustive list of where I found those window position preferences:

• ~/Library/Preferences/{appId}.plist
• ~/Library/Saved Application State/{appId}.savedState/windows.plist
• ~/Library/Containers/{appId}/Data/Library/Preferences/{appId}.plist
• ~/Library/Containers/{appId}/Data/Library/Saved Application State/{appId}.savedState/windows.plist

Where appId is the application ID, aka its bundle identifier, e.g. com.apple.mail for Apple Mail.

Resetting the window position

Now you were able to locate the preferences file for your app’s window location, you can reset it! There’s a few ways.

For the ones in Prefererences, this is typically managed (and cached) by the defaults command. The cached part is important: while you can manually edit or remove those files, your changes are more likely to be ignored until you reboot. To avoid that, use defaults(1) to edit them.

For Activity Monitor, that would be:

defaults delete ~/Library/Preferences/com.apple.ActivityMonitor.plist 'NSWindow Frame main window'

Which is equivalent to:

defaults delete com.apple.ActivityMonitor 'NSWindow Frame main window'

defaults delete com.apple.mail

As for the Saved Application State files, they don’t seem to be cached, and they’re definitely not editable with the defaults command, so feel free to remove them, or edit them with your favorite plist editor!