Hello,
I make some others trials.
A friend, developer, analyzed my two sites a bit.
In the production version, the component does not have an add / delete / edition rights configuration file ... whereas in the new version it looks like you have added one.
Which implies therefore that you added functions in the component to manage these rights and what I tell myself is that on this "detail" page of an entry (http: //preprod.seo-systeme. fr / extra / directory / 102-think-tank-g-nova.html), this must be (maybe) incorrectly set in the code
Or there is a kind of conflict between your code and joomla, which may explain the fact that one has access to the edition of a file ...
On your site, you indicate that this ACL management is present since 1.3.2.
Now my version in production is in 1.1.13 therefore lower:
Https://www.sigsiu.net/center/applications/5-acl-override-application
So in my opinion this comes from this new feature that is poorly managed from the detail record, maybe.
Could you test an update of component 1.1.13 directly to your latest version?
Without making any intermediate updates, I make it clear.
Thanks