XF 2.0 bb_code_tag_img - from which post?

[MrFreeze]

How can I tell from which post this image originates?

 

[Jeremy P]

That information doesn't seem to be available inside of that template, if that's what you're asking. All you have are the URLs. BBCode can be used outside of posts (including arbitrarily inside templates) so I don't think there's generally an expectation of being able to fetch context inside of their respective templates.