Topic
Users are getting 'Process Changed' or 'Process Archived' notifications in their 'My Changes' dashboard for the processes where they are not the participants /are not involved in any manner.
For, example a user is getting process change notification for a specific process where they are not an owner/expert or RACI stakeholder for that process. Or, their roles are not involved in the swimlane/activity of that process but still getting the change notification and their Involvement show as 'Viewer' in their dashboard.
Resolution
The users are getting the change notification because the configure called Users with viewing permissions are participants in accessible processes is turned ON under Admin > Configure > Viewing Options.
This means that if a specific process group has 'All Staff' role viewing permission where the users can simply view the processes under that group and with the above configure enabled, those users will also become participants of those processes but just as a 'Viewer'. More specifically, by enabling this configure users who can view a process will also be considered participants of that process even if they are not the owner/expert or RACI stakeholder or their roles are associated to that process.
So to prevent such change notifications of processes to appear in the users' (who can just view those processes) 'My Changes' dashboard, the configure Users with viewing permissions are participants in accessible processes needs to be turned OFF.
Additional Information
The below useful information is provided by clicking the 'Question Mark' icon from the configure itself under Admin > Configure > Viewing Options.