Jeff Johnson is the hero of StopTheMadness, Link Unshortener, and other must-have browser and social media utilities that allow you to block and stop websites from taking control of your cursors, mouse, and Control-click. (I gave StopTheMadness 5 out of 5 stars in a Mac Gems review last year.)
But what has he done for us lately? He figured out how to disable smooth scrolling, an unexpected feature Apple added in Safari 16.4 for macOS. In case you haven’t noticed, in this version of Safari, pressing and releasing the down or up arrow on a Safari page continuously scrolls the page until you press a key or use your mouse to regain control. The change is confusing. Who asked for this? Why inject it in the middle of a stream? And the biggest question is why is there no checkbox to turn it off?
Johnson documented a multi-stage operation to correct this problem. You can read his short post or a more detailed walkthrough here if you’re not familiar with Safari’s debug mode and the terminal.
- Completion time: 5 minutes
- Required Tools: macOS, Terminal app.
- Materials required: Safari 16.4
System settings/preferences

Foundry
macOS Ventura: Open > System Preferences > Privacy & Safety and go to the “Privacy” section (shown above).
macOS Monterey and older: Open > System Settings > Safety & Confidentiality and click on Confidentiality section to open it.
Full disk access

Foundry
macOS Ventura: Click Full disk access (shown above).
macOS Monterey and older: Choose Full disk access in the left column. Click the padlock icon in the bottom left corner of the settings window and authenticate with Touch ID, password, or watch.
Activate terminal

Foundry
macOS Ventura: Search Terminal in the main window and turn on its switch (shown above). After toggling the switch, you will need to enter an administrator username and password.
macOS Monterey and older: In the main part of the window, you will see a list of applications. Press the “+” button and go to Applications > Utilities. There you should find the Terminal application; select the terminal icon and then click the button Open button.
Close System Preferences/Settings.

Foundry
In both macOS Ventura and Monterey:
- Exit Safari if it’s open.
- Launch the Terminal app (located in Applications > Utilities).
- Copy the exact text below in one line, paste it into the Terminal when prompted, and press the “Return” key:
defaults write com.apple.Safari IncludeInternalDebugMenu -bool true
Safari debug setting

Foundry
In both macOS Ventura and Monterey:
- Exit Terminal and launch Safari.
- From the new Debug menu that appears, select Debugging > WebKit Internals > Smooth Keyboard Scrolling Controlled by EventHandler. It should have a checkmark, so selecting it will remove the checkmark and disable the option.
When you activate Safari’s debug menu, it stays active even after setting smooth keyboard scrolling. If you want to remove the Debug menu, repeat step 4, but instead copy and paste this command into a terminal and press Return:
defaults write com.apple.Safari IncludeInternalDebugMenu -bool false
Thanks to Johnson for revealing a hidden secret that should be installed in Safari!
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