Hello,
Thanks for your help. Yes your plugin is active on this site. Yes the header was created using UAE. You can see the header perfectly working on all pages except the pages belonging to the “Séance” category..
However, the preview when logged into the site administration works normally (you can see the headers). I’ve obviously cleared the cache several times and reloaded the pages (ctrl+f5). Another oddity on the affected pages is that the body images don’t load.