Large merge request blocks GitLab from deleting it

We have a repo where the main branch is not master to emphasize to the devs the branching model. This mean that all branches we create do not originate from master. Additionally, the main branch is kept as "master" in gitlab.

While this organization is used to force users to think about which branch they are in, it failed us on one point. The default branch is the one used by default during a merge request. We thus ended up with two merge requests to master, which is empty. Selecting the merge request will timeout with a 502:

502

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Please contact your GitLab administrator if this problem persists.

since the diff between the two branches is huge.

Increasing the GitLab's timeout might allow us delete the bad merge request, but this might not even be sufficient since the diff could still create issues.

Is there any other way to delete these bad merge requests without having to go on the command line? The installed instance of GitLab is, let's say it that way, not easily accessible.

There should be a "Close" button next to a merge request, similarly to the issues list, that would allow closing such merge requests without visiting the actual page. An "Edit" button could also be added, also similar to the issues list, to change the merge request.

Thanks!

Using GitLab 7.3.2 on CentOS 6.5 x86_64, installed through omnibus.