When sharing job ads on social media, either on LinkedIn or Facebook the sharing image is fetched directly from the job ad. However, both of these channels cache all pictures if the link has been shared before. This can result in the incorrect picture being displayed in the sharing thumbnail when a job ad's picture is updated and shared on social media again, due to the fact that the old picture is saved in their cache.
Once this has been done, the correct sharing image should appear in the thumbnail 🎉
LinkedIn Post Inspector
To scrape the information LinkedIn has store on your link, follow these steps:
Go to this site 👉 https://www.linkedin.com/post-inspector/
Paste the link in the URL field (1)
Click Inspect (2) and you'll see what the shared link will look like (3)
If the picture isn't updated, try refreshing the page with a hard refresh - Windows: Ctrl+F5, Mac: CMD+Shift+R