When copying an issue, the user can change arbitrary values before saving the copy. It is also possible to add attachments here. Before this patch, such attachments were added to the journal entry that is created to hold the "copied from" relationship change.

Since no other attribute changes are journalized, but only added attachments, we found that to be confusing. The attached patch which has been extracted from "Planio":https://plan.io/redmine-hosting prevents that from happening by checking for copy? in Issue#attachment_added.