for some reason, FB seems to do two things :
a link that looks like this: https://joseph-balson.com/Gear-Essays/S ... e-1c5LAJZ0
- ends in 404 error
a link that looks like this: https://www.joseph-balson.com/Gear-Essa ... hrs1ekSdcM
- works correctly
seems the issue is the / before ?. Maybe something can be done in the htaccess to fix that?