[SOLVED] Menus not rendered

Sorry to ask but I’m getting crazy.
On this repo:

I don’t get the ‘header’ menu to show up, it’s only after I go edit one of the files that should be in the menu that it appears after the live reload, then I stop the server, restart and the menu doesn’t show the entries anymore…

I tried multiple version of hugo, including the very latest but still no luck…

I would appreciate some help.

(I tried without i18n, same problem…)

FWIW if I remove my content/index.md then it seems to work properly for the other elements of the menu. ie: they are always displayed properly

renaming content/index.md to content/_index.md worked, I have no idea why