When users want to post a link without checking "no thumbnail", it doesn't work

Hi,

My question is about BuddyPress Activity +.
- As the admin, the plugin is working perfectly.
- But for my users, there is a problem whenever they want to post a link: they can't post it unless they check "no thumbnail".

Any idea?

Maybe it's the same kind of problem that is described here?
https://premium.wpmudev.org/forums/topic/whenever-we-post-a-link-the-preview-shows-up-but-when

Best Regards