I’m not sure that the problem is only the facebook app. Because I have this problem only from 2 or 3 days and only on the last articles I’m publishing.
All the previous articles have no problem with the images if I open them in the browser of the facebook app, everything is perfect.
Only the last ones have problems, and if I open the links inside the facebook browser application it shows me only the alternative text of the images in the content of the page, while the main image of the article (featured images) and the images in any widgets have no problems, only images in the content show the alternative text.. (for example if I have an image with a flower in the content, it does not show it, but it only displays the alternative text “flower” and the icon of the broken image)
It seems as if some updates caused it, but I can not understand what, if a plugin update… or a cash problem.
I don’t think it’s an open graph problem… I can try to download an open graph plugin, but I think if that was the problem I would not have seen any image of the article, not even the featured image.