Component Shadowing is a feature introduced in Gatsby Themes that allows users to override and customize components within a theme without needing to alter the original theme code or maintain a fork. This approach offers flexibility for making quick, specific changes that are not supported by default configurations, such as modifying the Bio component in gatsby-theme-blog. By creating a file with the same name and path as the original component within the user's site directory, Component Shadowing renders the customized version instead. It applies not only to React components but also to JavaScript, Markdown, MDX, or CSS files, enabling users to adjust design tokens like font sizes and colors. While it provides a convenient way to customize themes, extensive use of shadowing may suggest the need for a code fork. Future updates will enhance tooling to track shadowing occurrences and manage the customization process better.