Yes, I saw this option, thank you, but it's not what I actually need because it displays original images. Several digital photos attached in a topic might easily make opening it quite a bandwidth consuming task.
For example, SMF deals very nicely with image attachments: it creates small thumbnail images during the upload and displays them inline in posts. Only when a user clicks on thumbnails, the original image is loaded and displayed.
Alternatively, could you maybe advice other solution? I tried several unofficial extensions and mods like "image upload", but they were either outdated or just didn't want to work.