Though a Stakeholder in Azure DevOps can read and access Wiki pages in a private project. They won’t be able to edit the pages or reorder or revert the changes to the Wiki pages. (Even if they are added under Project contributors they won’t be able to edit or add new pages in the Project Wiki). In addition to that if your Wiki is a code wiki they won’t have access to even read it in addition to the other permissions limitations.
To enable a Stakeholder to access , you need to change a user from Stakeholder access to “Basic” access in the Organization settings of Azure DevOps. This can be done only by a Project Collection Administrator who are otherwise known as “Org” Administrators.
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