https://instant-issues.github.io/
A blazingly fast client-side search for GitHub issues. For enabled repositories all open issues are regularily aggregated to a single JSON file, which is downloaded by the client.
To enable Instant Issues for a repository you just need to create a YAML file with the upstream workflow.
If you want to use Instant Issues with repositories where you do not have write access, you can create a new public repository and use the downstream workflow. You will need to tag your repository with the instant-issues-downstream topic for it to be discovered by the frontend.
Issues and pull requests are welcome!
Because GitHub has a tight Content Security Policy we cannot patch the issue search within github.com with a UserScript. A browser addon would have the necessary privileges but it could also access your GitHub cookie, which is undesirable from a security perspective.