Hi @Nicky Ferkins ,
As I know, we couldn't display a linked picture directly in message preview, and it would display the link code like below if there's a linked picture in the first few lines of the message body and we set the message preview to 2/3 lines:
If it's your case, it's suggested to change the setting to 1 line or Off(View>Message preview).
Hope that would be helpful to you.
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