How to Astutely Use OS X Hot Corners Without Consternation

Hot Corners on the Mac have been around for–ever. Have  you tried them? Long-time and newbie Mac users whom I have taught over the years, are surprised to discover Hot Corners. So, I thought I’d go over this practical feature with my TMO readers.

The top-left corner of the Mac screen

The Hot Corner is the pixel at the very corner of the screen. The action is fired when the apex of the pointer meets this “hot” pixel.

At each of the four extreme corners of your Mac screen there is a “hot” pixel. These Hot Corners can be programmed to kick off an action as soon as the pixel at the apex of the mouse pointer is placed over that Hot Corner pixel. For you Mac terminology enthusiasts, Hot Corners are also known as Active Screen Corners.

As we often discover, Apple provides us with many handy features that are not obvious and often not documented well – or at all. The Hot Corners feature itself has a hidden but very important characteristic that eliminates the one annoyance that Hot Corners can cause.

Let me explain as we jump in and take a look.

Activating Hot Corners

Hot Corners does not have its own System Preferences panel, but it is accessible via either of two other ones in System Preferences. You will find a Hot Corners button in the Desktop & Screen Saver Preferences (the Screen Saver pane) and in the Mission Control Preferences.

Clicking on the Hot Corners button will reveal the Active Screen Corners configuration pane. 

The Mission Control Preferences panel and the Active Screen Corners pane.

The Mission Control Preferences pane is one of two ways to configure Hot Corners. The other way is via Desktop & Screen Saver Preferences

Clicking on any of the four popup menus will reveal the choices you have for assigning actions to their respective four corners.

The Active Screen Corners pane with an open popup menu.

Each Hot Corner can be configured via a popup menu

Beating the one annoyance with Hot Corners

Recall that I mentioned an annoying aspect regarding the use of Hot Corners. The problem is that when “mousing around” the screen, the pointer often tends to inadvertently touch those corners. The action associated with that Hot Corner will fire (wow, a pun), and cause you a great deal of perturbation. More often than not, your vexation will cause you to seriously consider forgetting about the whole Hot Corner thing. 

Hidden feature to the rescue!

You can add a Modifier Key (Control, Option, Command, or Shift – singly or in any combination) to help you avoid the frequent accidental activation of Hot Corner actions. To do this, while configuring a Hot Corner, press one or more of the modifier keys. You will see the corresponding key symbol appear next to the Hot Corner action listed in the popup menu.

For myself, I prefer using the Option key when I need to activate a Hot Corner. In case you’re wondering, here’s how I’ve configured Hot Corners on all my Macs:

The Active Screen Corners pane

Pressing modifier keys while selecting a Hot Corner action will display the symbol in the popup menu item

Yes, I am one of those handful of people who find some Dashboard widgets useful: Dictionary, Stickies, Stocks, Unit Converter, Weather, Delivery Status (by Junecloud).

Special consideration for activating the screen saver

Setting up a Hot Corner with a modifier key to activate the screen saver on demand was frustrating at first. Eventually, I found the correct sequence to get the screen saver Hot Corner to work as expected:

  1. Press the modifier key
  2. Move the cursor to the Hot Corner
  3. Immediately release the modifier key (before the screen saver activates). If you wait too long and the modifier key is still depressed when the screen saver kicks in, it will deactivate as soon as you release the modifier key. Most tiresome.

Hot Corner functions

Many of your choices for Hot Corner functions are self explanatory: Mission Control, Dashboard, Notification Center, Launchpad, Start/Disable Screen Saver, and Put Display to Sleep.

One of my favorites, the Desktop option, allows me to quickly access my Desktop while hiding all windows. Of the four Hot Corners, I tend to use this one the most because I often use the Desktop as a staging area for files. 

Even with this function engaged, where all the application and document windows have swung out of the way temporarily, I can drag and drop files from the desktop back into the open documents if their respective applications support this. This is done by dragging the desktop file back to that same Desktop Hot Corner. The open apps and documents swing back into view, and I can drag-and-drop the image file onto the document. For example, I do this quite often for adding images to Pages and Keynote documents.

Finally, I also like to have the Application Windows option configured for one of my Hot Corners. This lets me not only see and access all the open document windows of the frontmost app, but I can also see and access thumbnails for all my recently opened files. 

The Mac screen after activating the Application Windows Hot Corner

This is what I see when activating my Application Windows Hot Corner while in Pages

For instance, I often work in Pages with several document windows open. When I move my cursor to the designated Hot Corner to bring up all document windows, I simply click on the one I want to activate. For me, this is a much quicker method than using Pages’ own Window menu or the Open Recent menu.

In conclusion, why not try all these options out. See which ones might work best for you and for augmenting your own workflow. Don’t forget to use the hidden modifier key trick. That will go a long way towards helping you use your Hot Corners stress-free and efficiently.