How to disable sidebar in all apps

The sidebar has no global control in the Mac. It can be hidden or shown in some apps. For example, in Finder, the sidebar can be hidden and unhidden using control-command-S (⌃⌘S) or by going to the menu View > Hide (or Show) Sidebar.

In Safari browser, the same Hide/Show command can also be found in the View menu, but the shortcut is shift-command-L (⇧⌘L).

Check the View menu of other apps or search the Help menu in those apps for more information.

You can leave product feedback directly to Apple or submit a request for features consideration using this link: Product Feedback - Apple

What apps are you talking about?

Each app has its own settings. As D. I. Johnson said, there is no general setting for all apps, and that would not even make sense, IMO. Not all apps have the notion of sidebar, and they all have different functionalities.

At least in most apps, you can control how they behave in this regard, and once you set them up, they should honor your settings.

For example, what you can do in Preview with the sidebar is different from Mail, or Finder.

In Finder, you just do Hide Sidebar (or Command-Control-S) and then any new window you open will not show the sidebar.

In Preview, it is similar (though if you choose to open multiple images in the same window, then it will still show the sidebar, which makes sense - it is the obvious to navigate between these images; but even then you can hide it with Command-Control-1).

The details vary, but mostly you just turn off and it will stay off, not for all apps, but in each app. There aren't all that many.

badapples23 wrote:

Having sidebar open everytime in an APP is super annoying. Why can't I disable it for all apps? So tired of Apple assuming they know what I want!!

Can this be preemptively disabled?

Never heard this unique request before...

And what is the functionality of hiding an app sidebar anywhere, what is the benefit as you see it...(?)

Any examples?

Maybe if you paint a bigger picture of how this fits into your work flow. Otherwise it is hard to grok the rational for some universal setting.

Is there some bigger issue associated here that you do not mention??

The current stable release of Tahoe including bug fixes, security updates is macOS 26.5

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