Finder: Open new window when double-clicking on folder?

The answer is simple: if you hide the window toolbar, you will get the behavior you describe. As a side effect, the Sidebar will also disappear; you essentially get the classic “spatial Finder” behavior where there is a one-to-one correspondence between windows and folders.

docfi wrote:

Does anyone know of a Terminal command that will change the Finder's behavior so that when you double-click on a folder it opens in a new window? That is to say, without holding down the Command key. Years ago, this was a selectable option.

Thank you.

Change how folders open in the Finder on Mac - Apple Support

Get to know the Finder on your Mac

https://support.apple.com/en-us/HT201732

See and organize your files in the Finder on Mac - Apple ...

https://support.apple.com/guide/mac-help/finder-mchlp2605/mac

The term "spatial Finder" was used a long time ago to distinguish the way the Finder used to work in Mac OS 9 and earlier: each window was not a view on a folder, it was the folder. When Mac OS X came along, around 2000, the way the Finder worked changed, so it became not so much identified with the file system, but acted more like a browser for the file system.

It introduced column view, for example - I remember I was perplexed with it, and it took me a while, but now is my favorite :-)