Notification beta filter drop-down auto completion is overlapping #2705

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• I disabled both Refined and GitHub Dark turning them on and off. This is definitely located in Refined GitHub.
• https://github.com/notifications/beta?query=is%3Aunread\ With Refined GitHub enabled. With Refined GitHub disabled

I located the issue, it's related to the form parent element being set to a display: flex instead of how GitHub intended it to be display: block

This is the CSS in question.

https://github.com/sindresorhus/refined-github/blob/cfbc2d4c7166eea2bd4d653ff93a746b87e53d93/source/features/widen-search-field.css#L16-L24