GitLab B.V. CEO here, consider using GitLab, it adds a cross-reference when you reference another issue (can be in the same or another repo, even across organizations).
i can't stand when a tech company can't innovate their own webpage more than using a standard Bootstrap template any noob developer can use. No offense to your product I'm sure it's great. I just don't understand why every company, especially in the tech field can't even design their website to be just a little bit unique.