Attachments no longer display

Hello,
I noticed yesterday that attachments were no longer showing up in my browser (blank screen with Google Chrome and “Content Encoding Error” message with Mozilla Firefox).
See for example here: https://www.un-jardin-bio.com/?wpsc_attachment=2689&tid=1715&tac=3D4Gga5a56
I also tested setting “Download” for attachments, but then it says “Failed – Network Error.”…
It was working fine 3 days ago…
Since then, 4 plugins have been updated on my site (Specific Content for Mobile, All Is One WP Security and Firewall, Contextual Related Post and Thrive Leads)… I disabled these plugins to see if the problem could come from one of them, but that doesn’t change anything.
I specify that the ticket system is accessible only to members of my site (with Login and Password)… so I cannot give you the URL of the page here (you could not have access to it); but I can create temporary access to my wordpress dashboard for you to see this.
Thank you for your help.

The page I need help with: [log in to see the link]