You can now specify whether to display images for light or dark themes in Markdown, using the HTML <picture> element in combination with the prefers-color-scheme media feature.
For example:
<picture>
<source media="(prefers-color-scheme: dark)" srcset="https://user-images.githubusercontent.com/25423296/163456776-7f95b81a-f1ed-45f7-b7ab-8fa810d529fa.png">
<img alt="Shows an illustrated sun in light color mode and a moon with stars in dark color mode." src="https://user-images.githubusercontent.com/25423296/163456779-a8556205-d0a5-45e2-ac17-42d089e3c3f8.png">
</picture>GitHub Advanced Security customers can now dry run their secret scanning custom patterns on all repositories within an organization. Previously, admins could only dry run on a maximum of 10 selected repositories.
Learn more about secret scanning
Learn more about defining custom patterns
GitHub Pages now builds with GitHub Actions by default across all repositories.
For more details, see this blog post.