How to output an image from an ad to an e-mail template? Found only one mention in os-includes about '{ITEM_IMAGE}' => __('Listing image'),

@atba
If image keyword would be present, then it would be just URL, so you would do it like:
<img src="{ITEM_IMAGE}"/>

This code does not work

Really none of the users and you, how are developers not interested in such a detail as an ad image in an e-mail template? On all known bulletin boards, this is by default. If you don't have time, tell me which file requires edits to make {ITEM_IMAGE} work?

I do not see it used in any of defaul template.
It's just legend title.
Osclass does not populate this variable in any of email templates.

I do not see it used in any of defaul template.
It's just legend title.
Osclass does not populate this variable in any of email templates.

What does the templates have to do with it? The point is that this legend does not work!

it's legend. I can put whatever into legend.