Confusion when viewing diffs of a specific commit

Summary

If you follow a link to a specific commit in an MR it is not evident that you are viewing the diffs of the not most recent commit. This can be confusing when referencing rebase or other commits.

Steps to reproduce

• View this link of a commit reference to a specific MR
• View this link of the MR directly

If you weren't fully aware of the link you'd be confused by the diffs in the first link, especially because the MR files changed doesn't match that of the actual diff view.

Example Project

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What is the current bug behavior?

What is the expected correct behavior?

Is the direct example. But perhaps some way to flag to the user that they are not viewing the most recent commit in the MR when viewing diffs would be an improvement to avoid the confusion.

Relevant logs and/or screenshots

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Output of checks

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Results of GitLab environment info

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sudo gitlab-rake gitlab:env:info)
(For installations from source run and paste the output of:
sudo -u git -H bundle exec rake gitlab:env:info RAILS_ENV=production)

Results of GitLab application Check

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(For installations with omnibus-gitlab package run and paste the output of:
sudo gitlab-rake gitlab:check SANITIZE=true)
(For installations from source run and paste the output of:
sudo -u git -H bundle exec rake gitlab:check RAILS_ENV=production SANITIZE=true)
(we will only investigate if the tests are passing)

Possible fixes

(If you can, link to the line of code that might be responsible for the problem)