Link from merge request creation page on a repo's fork goes back to the original repo

Summary

A link on the create Merge Request page points back to the original repo, if you're looking at the repo on a fork.

Steps to reproduce

When I have forked a repo, and I push a new branch to my repo-fork, and then prepare a merge request

On the page where I prepare the merge request, there's a summary of the constituent commits

They have a hyperlink, but it links to a commit blob which is in the main repo, not my fork.

My expectation was that they would link to a commit blob in my fork. I was also expecting that my commit blob wouldn't be in the main repo's history at all.

What is the current bug behavior?

They have a hyperlink, but it links to a commit blob which is in the main repo, not my fork.

What is the expected correct behavior?

My expectation was that they would link to a commit blob in my fork. I was also expecting that my commit blob wouldn't be in the main repo's history at all.

Relevant logs and/or screenshots