Can Mail.app be configured to always load remote images from certain domains?
Short answer

There is no specific option for this. But you can define a rule and run an applescript.

Solution


Save applescript below with any name and to any folder you want.
Go to Mail app &gt; Preferences &gt; Rules and click Add Rule. Give name theRule to your new role and select conditions that you want to display remote images. For your question this should be From > allsongs@n.npr.org.


You could also select Sender is in my Address Book to display remote images for all mails come from  your contacts.

Under Perform the following actions: section, select Run Applescript and choose the file you wrote at step 1.
Save the rule.


Applescript

--BEGINNING OF SCRIPT
using terms from application "Mail"
on perform mail action with messages theMessages for rule theRule
tell application "Mail"
activate
repeat with eachMessage in theMessages
open eachMessage
tell application "System Events" to tell process "Mail"
set loadButton to a reference to button 1 of UI element 1 of row 1 of table 1 of scroll area 1 of front window
if loadButton exists then click loadButton
end if
end tell
end repeat
end tell
end perform mail action with messages
end using terms from
--END OF SCRIPT