Disable Notifications - Airmail for macOS
You can disable the notifications for Airmail in two ways.
System Preferences
Notifications for Airmail can be disabled from System Preferences which is illustrated in screenshot below:
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Notifications for Airmail can also be disabled from Airmail itself by clicking Preferences > General > Notifications and the same has been illustrated here under:
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Additionally, Airmail also allows its users to disable notifications for one particular account by steps as Preferences > Accounts > More > Notifications. Please refer to the picture below:
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System Preferences
Notifications for Airmail can be disabled from System Preferences which is illustrated in screenshot below:
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2. Airmail Preferences
Notifications for Airmail can also be disabled from Airmail itself by clicking Preferences > General > Notifications and the same has been illustrated here under:

Additionally, Airmail also allows its users to disable notifications for one particular account by steps as Preferences > Accounts > More > Notifications. Please refer to the picture below:
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Updated on: 01/11/2019
Thank you!