I’ve mentioned this issue before but I just can’t seem to fix it.
Our system uses a fallback image for all posts created without a featured image.
When users submit a post through Post Creation form, an image is required.
So far, so good.
When a post is created with the form, the featured image shows up on the site as normal. No problems.
However, if the post URL is pasted into Facebook, the image shown is the fallback image! This does not happen if a post is created in the normal way via the back end.
It’s as if the featured image is being saved - but not saved…?
In order to correct this bug, once a post has been created using the form, it is necessary to go into the admin area and manually re-save the post. Once this has been done, it is then possible to paste the post link into Facebook - which will now show the correct image.
Are you using any SEO plugin? If so, it might be generating OG tags for social sharing, which could be causing the issue.
You can add the following code to your child theme’s functions.php file or use any Code Snippets plugin. Then, visit https://yoursite.com/?force_cron if the code doesn’t run automatically. This URL will force the cron to run. I have tested it, and it worked on my end.