Clicking an FTP link on a PR overview page opens the PR page instead of the ftp site

Issue Summary

ftp :// links do not open in Bitbucket 7+, but reopen the PR overview page on a different tab

Steps to Reproduce

1. Create a PR
2. In Overview (http://<BASE_URL>projects/<project-key>/repos/<repo-slug>/pull-requests/x/overview), write a new comment including a link to a file from an ftp server such as ftp://xxxx/file.txt, and save
3. Click on the link

Expected Results

A new tab opens for URL ftp://xxxx/file.txt

Actual Results

The new tab displays once more the overview page http://<BASE_URL>projects/<project-key>/repos/<repo-slug>/pull-requests/x/overview

Workaround

Copy-paste link on a different browser tab