One possibility is that if the picture is linking from another space where you do have access permissions but the other users don't, then that would mean that they can not see the attachment.
Try uploading the picture directly from your storage device.
Hi my Community friends! For those who don't know me, I'm a product marketer on the Confluence Cloud team - nice to meet you! For those of you who do, you know that I've been all up in your Co...
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