How to fill a bug about the hosted gitlab.com instance?

Hi, I found some bugs on the gitlab instance hosted on https://gitlab.com/ , one of them is critical since it breaks branch merging, how can I report these bugs and where?

If this is a security issue send an email at contact@gitlab.com. If this is a regular one, open an issue at https://gitlab.com/gitlab-org/gitlab-ce/issues. Do you by any chance have the same problem as https://gitlab.com/gitlab-org/gitlab-ce/issues/2026 ?