allow_upload not possible for restricted users

[gogobd]

When a user has no (View, Access Contents Information) permission between the Plone root and another folder whre they do have permissions @@allow_upload fails (allow_upload is being called on the Site root)

Example:

/a/b/c

User has no access on b but is allowed in c, /@@allow_upload gets a 302.

What actually happened:

302 Errors visible in "Network" in Developer Tools (xhr)

What version of Plone/ Addons I am using:

Plone 6.0.11 and newer, plone.app.content 4.1.2

Possible reason

In plone.app.content 4.1.2 (and 4.1.8 i.e. master) we use restricted traverse, and it's unclear why - using unrestricted traverse might just fix this issue.

https://github.com/plone/plone.app.content/blob/0eca90492d3e942fe84813861b6fb273fe405899/plone/app/content/browser/file.py#L193