If you Airmail app is running slow, there are following methods to speed it up; either through account specific settings (only applicable to a specific email account), or universal settings (applies to app in general).
Universal App Settings
1. Open the Airmail app
2. Open Airmail Preferences (⌘,)
3. Go to the Advanced Tab
4. Advanced Graphics Option:
- Deselect "Animations and Transparency" to disable Advanced Graphics. This will only take effect once you restart the app
Account Specific Settings
These settings only applies to a specific account. If you have multiple accounts, these changes have to be made per account.
1. Open Airmail Preferences (⌘,)
2. Select the settings icon of the account you want to edit.
3. Under the More Tab
- Folders Refresh: Set this to a longer timing
- Download: Deselect "Attachments" (This will stop the automatic download of attachments)
- Reset Account: Click on Clean Message Cache. This will reset and re-initialise the account.