### Summary Error is being displayed when previewing changes from the New MR page (before creating the MR) ### Steps to reproduce On gitlab.com (Next) 1. Create new MR 2. Click Changes tab <!-- Describe how one can reproduce the issue - this is very important. Please use an ordered list. --> ### Example Project Any project <!-- If possible, please create an example project here on GitLab.com that exhibits the problematic behavior, and link to it here in the bug report. If you are using an older version of GitLab, this will also determine whether the bug is fixed in a more recent version. --> ### What is the current *bug* behavior? Error is displayed `MergeRequest|Failed to load the page` Also scrolls to the top of the page, see: https://gitlab.com/gitlab-org/gitlab/-/issues/387275 <!-- Describe what actually happens. --> ### What is the expected *correct* behavior? No error displayed <!-- Describe what you should see instead. --> ### Relevant logs and/or screenshots  <!-- Paste any relevant logs - please use code blocks (```) to format console output, logs, and code as it's tough to read otherwise. --> #### Results of GitLab environment info gitlab.com Next <!-- Input any relevant GitLab environment information if needed. --> <details> <summary>Expand for output related to GitLab environment info</summary> <pre> (For installations with omnibus-gitlab package run and paste the output of: `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`) </pre> </details> <!-- If you can, link to the line of code that might be responsible for the problem. -->