The portal administrator may have run the script
serlacl.sql to enforce role-based security. Role-based security limits privilege grantees to groups; users cannot be selected for privilege assignment. The script does not affect privileges granted to users before it was run, only after. You may also note that the Browse Users icon does not appear next to the Grantee field on Access tabs.
For more information, see Oracle Fusion Middleware Administrator's Guide for Oracle Portal.
It is not enough to have the Manage Style privilege on a page. The page group option Allow Privileged Users To Manage Page Style must also be selected for the page's page group. For more information, see Section 4.3.2, "Controlling Who Can Apply a Different Style to a Page".
Tab level access is overridden by page group level access settings. To prevent users from seeing content on a specific tab, you must make sure that they do not have higher privileges on the containing page group.
If the page is based on a template, and template access is set up to prevent users from applying styles to pages that are based on the template, the Style tab cannot be accessed in the page properties of pages based on the template.