argoproj.github.io - Page not found when returning to previous page

This was initially reported on https://github.com/webcompat/web-bugs/issues/56673

**URL**: https://argoproj.github.io/projects/argo-cd

**Browser / Version**: Firefox 80.0
**Operating System**: Windows 10
**Tested Another Browser**: Yes Edge

**Problem type**: Something else
**Description**: Clicking on "argo rollouts" leads to rollouts. Then clicking back leads to rollouts again, only that this time it hists a route which does not exist.
**Steps to Reproduce**:
Clicking on "argo rollouts" leads to rollouts.
Then clicking back leads back.
Automatically I am sent to rollouts again, only that this time it hists a route which does not exist.

This does not happen with other browsers.

View the screenshot

This also reproduces on Safari.

Start by reproducing the navigation from https://argoproj.github.io/projects/argo-cd in Firefox and Safari: open “argo rollouts,” then use the browser back action and inspect the resulting URL. Done means returning to the previous page no longer redirects to a nonexistent route.

Written by the indexing model from the issue text.