The ‘recently used apps’ feature in the Mac Dock displays up to three apps you have recently opened but haven’t permanently added to the Dock, making it easy to relaunch them quickly.
This section appears to the right of your pinned apps, separated by a divider, and updates automatically as you use different applications. You can use a terminal command to place your more recently used apps in the Dock.
Enable recent used apps in Mac Dock
- Open ▸ System Settings
- Go to ‘Desktop & Dock’
- Enable the option ‘Show suggested and recent applications in Dock’

Adjust the number of recent used apps in Mac Dock
Copy and paste the following command into Terminal and press ENTER to execute the command.
defaults write com.apple.dock show-recents -bool true; defaults write com.apple.dock show-recent-count -int 5; killall Dock
After executing the command, the number of three recent apps will be changed to five. Is this still not enough? Then you can change the 5 in the above command to any desired number. Use 3 to change the number to the default settings.