This has been happening since the recent forum update. The [ preview=* ] sCode tag doesn't work anymore. I checked the html for one of my posts and it's not even a broken image, there's just nothing there:

The weird thing is that if I edit my post, the previews start showing up on the page when it updates my post. The preview tags were there the whole time, but they don't show up until I submit an edit (even if I don't change anything).

Except then when I refresh the page, they disappear again. So all the preview threads we make are functionally useless until this bug is fixed. :/

I noticed this too :/