The most recent reply by the OP should address that → Après avoir forcer le https pour mon site, j’ai un problème - #6 by thejazzhour
From what I understand he simply set the database host to an empty string and this - presumably - defaults to localhost which avoids the DNS resolution to Cloudflare’s proxies and goes straight to the local database setup. That is all speculation as I do not know the exact setup and am not really familiar with Joomla either, but thats how it seems at least 