Redmine

Copied from #4618 which is closed but still appeared on Redmine version 3.4.5

Steps taken that produce this behavior,

1. An issue has an attachment made to it (usually in my case, a screenshot)
2. Another attachment is made, with the same filename as the one from above.

At this point, the new image replaces the other one, and references to it now point to the new one. What I'd want to see is that the new attachment gets renamed so that it doesn't displace the old one.

Very problematic for issue comments with embedded screenshots: the newer screenshot automatically replaces the old one so makes the old comment confusing/useless without the old original screenshot that the comment was intended for, essentially changing the comment history.

Extra information:

Redmine version                3.4.5.stable
Ruby version                   2.3.7-p456 (2018-03-28) [x86_64-linux]
Rails version                  4.2.8
Environment                    production
Database adapter               Mysql2