Hello @letrollpoilu
I'm facing the same issue as yours today as the leaaflet map is displayed in an authenticated session but not when I'm opening the page (permissions OK) in an anonymous session.
On your last comment, you're explaining the solution but the code in html.html.twig is the same as the code you're fixing.
So, what is the final solution ? May I have to report<js-bottom-placeholder token="{{ placeholder_token }}">
in another template ?
Thank you by advance for your help.