XF 1.4 Attachments are displaying as links instead of images.

[Stuart Wright]

This one is fine, displaying as an image:
https://www.avforums.com/threads/in...-picture-thread.1732561/page-22#post-21601720
This one is not, displaying instead as a link:
https://www.avforums.com/threads/in...-picture-thread.1732561/page-22#post-21609257

Why?

 

[Martok]

It looks like the poster hasn't inserted a thumbnail or full image so the attachment is displayed at the bottom of the post. It isn't showing a tiny thumbnail for this though. Search the ACP for "Attachment Thumbnail Dimensions" to see what is set for this.

 

[Mike]

It looks to me like there was no thumbnail generated for the image. This would indicate either the image failed to thumbnail (due to issues while thumbnailing; I've seen this with Imagick at times, usually a config issue) or that the image dimensions were too large to process/thumbnail.