Open Fork button leads to dead page when Fork is deleted #4301

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Just noticed a small bug after deleting my fork of this repository - the quick open button next to the 'Fork' button is still present but leads to a dead page.

Template Questions

1. A REAL URL where the bug appears. If it happens on a private repo, find an equivalent public URL. A. https://github.com/sindresorhus/refined-github (in the state my GitHub profile is in)

2. A screenshot/video/gif of the issue, if it’s visual. A. https://streamable.com/xmlo6f

3. Any related errors in the browser’s console, if any. A. N/A