There are some apps that you may want to open automatically every time you start or login to your Mac. For example, if you use your Mac for, you may want to open the Slack directly to quickly. However, there may be some apps you don’t want them to automatically open when operating.
Stop apps from auto-opening by using System Preferences System Preferences
You can see all the applications that have been tuned to run automatically when you log on by accessing the System Preferences.
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1) click the icon for the Apple> System Preferences System Preferences from the menu bar.
2) Choose the users and groups Users & Groups.
3) Select your user on the left if you have more than one user.
4) Click on the login items Login Items on the right.
5) you will see all the elements for automatic operation. Remove one of these elements, select it and click the minus sign at the bottom.
Stop apps from automatic operation using the application bar Dock
If there was a specific application is in the operating state, you can change this quickly from the bar to the Dock bottom, assuming that application exists permanently or as a user recently.
1) right click or press Control and click on the app icon.
2) go to the options in the pop-up menu.
3) if the option of opening when you log on Open at Login is enabled, click it to deselect it.