Consider the following scenario.
A SharePoint Online user has at least Full Control permissions for a subsite.
The same user has limited permissions, or no permissions, for the site collection that contains the subsite.
When the user browses to the Site Features page for the subsite and then clicks Activate or Deactivate for the SharePoint Server Publishing feature, the user receives one of the following error messages:
Sorry, you don't have access to this page
To resolve this issue, have a site collection administrator activate or deactivate the feature on the subsite. Or, an administrator can add the affected user to the Hierarchy Managers group for the site collection that contains the subsite.
For more information about how to manage SharePoint groups, see Customize SharePoint site permissions.
his is the expected behavior in SharePoint Online. The user must have access to the parent site collection through the Hierarchy Managers group to activate or deactivate the SharePoint Server Publishing site feature for the subsite.
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