Hello,

I have enabled og:image for Facebook, but when I enabled it:

under K2's parameters -> image tab -> "Force 'item modified date' as URL timestamp on image paths"

og:image (and html meta "image" too) is not in head section. When I disabled timestamp, og:image is returning.

I need og:image with timestamp. Please help me.

(k2 v2.7.0, latest joomla).

Thank you for reporting this.
I can verify the issue. I have proposed a file change for the components/com_k2/views/item/view.html.php file -
github.com/getk2/k2/pull/337/commits/b07ba02712ee6ac131dfecdc6ed441c3ec872cde

Clicking on View will show you the entire file - github.com/getk2/k2/blob/b07ba02712ee6ac131dfecdc6ed441c3ec872cde/components/com_k2/views/item/view.html.php