Check your network logs when loading images from feddit.org.
It might be that feddit.org is blocking your requests for some reason as LW does not seem to be using the image proxy feature of Lemmy.
Try to learn how federation works if you don't know it already. Otherwise you'll be wondering why some problems occur, why some things are the way they are and why users and comms have a @example.com in their names.
I'm just trying to help. No need to sound like that, buddy.
!<comm_name>@<instance_domain> is the microsyntax for tagging communities, in Lemmy, Piefed and Mbin. No client will open your /c/code_review@programming.dev.
Summit. Very active and friendly dev.