I have the same issue. Some user (maybe have the Manager role) is able to create a wiki page and to save the page appropriately. In the same session the user wants to edit that page and save the changes. He get the same answer:
03120048 Wrapped Exception (with status template): 0312881750 Failed to execute script 'classpath*:alfresco/templates/webscripts/org/alfresco/slingshot/wiki/page.put.json.js': 0312881749 Access Denied. You do not have the appropriate permissions to perform this operation.
Only the owner of the dashboard site is allowed to edit and save changes!
I'm using CE 3.4.d (update from 3.4.a). If I trying a clean roll out of the box (bundle install), that behavior does not occur, but I'm not able to import my MySQL database + alf_data repository accordingly - I get errors of missing node IDs.
(Not to mention of course, that my backup 3.4.a is working correctly!!!!)
I think, that the SQL-patches during the first start of the new version are erroneous. Is the a way to correct that?
Help is much appreciated!