After the Editor Role UI personalization is configured to show the Development -> CSS stylesheet. It does not show anything inside the dashboard or in the application menu.
IU Personalization is not enough, you also need to configure Permissions.
I have search for the permission but not sure which part of the module to give read and modify permission.
Let's try to go from the other side:
Go to Modules -> Design -> User Interface -> navigate CSS Stylesheets -> Roles tab -> select appropriate site in site drop down -> check CMS Editor.
The CMS Editor Role is already checked there but the application menu does not show anything on the development.
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