User automatically added as watcher when autowatch disabled

Summary

Confluence adds a user to watcher to page although the user has disabled the autowatch. This happens when the user adds an attachment to the page.

Environment

Confluence 5.8.13

Steps to Reproduce

1. Login as a user who can add attachments
2. Go to the user profile and uncheck the autowatch option.
3. Go to a page and uncheck from watching the page (If you are watching the page)
4. Add any attachment
5. Check the watcher and you will be watching the issue

Expected Results

You are not added as the page watcher since autowatch is disabled

Actual Results

You are added as a watcher even when autowatch is disabled.