Jekyll error converting mardown extension to html for parent folders

[AbcSxyZ]

When you use a Markdown link to point to a parent folder, as in the case of the file contenu/modèles/open-education.md, which would point to the file ressources.md at the root with this link :

[Liste des ressources](/ressources.md)

Conversion problem with Jekyll and Github page, which does not convert the link into html, and will download a markdown file from a deployed site instead of displaying a web page.

Current solution: You can use a link directly with [link](/file.html), which will allow navigation from the site, but will break the navigation on the raw mardown.

Research:
Perhaps the problem could be solved with the Jekyll configuration, but nothing conclusive as I write. The "jekyll-relative-links" plugin, which is already enabled in _config.yml, is supposed to allow the use of a relative path (type ../../file.md), but the tests I've done don't work 🤷

Deploying a site with Github Pages without a custom domain name for a fork will certainly require a Jekyll config for baseurl and url, see: https://mademistakes.com/mastering-jekyll/site-url-baseurl/