When you read the details of a post, you can zoom on the included images (the mouse cursor change to a magnifying glass with [+] icon). That's OK!
But, when you read the same full message from browsing the list of messages:
- Home page > Latest Update: browse all > (A topic): See more
- you can read the posted topic and see the images in the topic
- there is also a magnifying glass cursor when you hover the images
=> but no zoom action in this case...