How do I prevent folders from opening in a small window on MacBook Air with Tahoe 26.6.2?

I am using a MacBook Air 15-inch M5, running Thole 26.6.2. I have noticed that when I double-click on a folder icon on the desktop, it opens as a small window. If I maximise the window size & then reopen the folder, it opens as a small window again. How can I fix this without resizing each window after I open it? I even tried using the Option key to close the resized folder window. It works a few times, and then it opens a maximised window. But again, the same problem.

[Re-Titled by Moderator]

Original Title: The folder window always opens small size, even after I resize it and close it with the "Option" button.

Posted on Oct 7, 2026 10:54 PM

1 reply

Owl-53

Level 10 (123,805 points)

Oct 8, 2026 3:50 AM in response to appajee

Since you are running macOS Tahoe 26.6.2, I would first update to macOS Tahoe 26.7.1,

if it is available under System Settings > General > Software Update.

It includes bug fixes and security updates, although Apple does not specifically say that it fixes the Finder window-size problem you are experiencing. Apple’s macOS Tahoe update information

After updating, restart your Mac and open the folder from the Desktop.

Use the green button > Fill to make the Finder window fill the desktop while keeping the menu bar and Dock visible.

Then close it with Command-W and reopen the same folder to see whether Finder remembers the size.

Apple calls this Fill, rather than Full Screen.

Also, Option-clicking the green button is different from closing the window with the Option key; it restores the window to its previous size. Move and arrange app windows on Mac

If the folder still opens small, there is not a Finder setting that Apple provides for forcing every folder to open maximized.

Finder's folder-opening settings deal with tabs and windows, while View Options control how the contents are displayed, not the window's size. Change how folders open in the Finder

If the problem remains after the update, the next step would be to troubleshoot Finder's saved window state rather than continually resizing the window.

I would treat that as a troubleshooting step rather than a guaranteed fix, since Apple does not document it specifically for this problem.