typedoc-custom-theme

Example of creating a custom TypeDoc theme, see src/index.tsx for code & comments.

Notes:

Do not specify typedoc as a dependency, but as a peer dependency. Specifying it as a dependency would result in multiple TypeDoc instances being loaded, which will probably break your theme.
TypeDoc 0.22.9 and later will automatically load npm packages with typedoc-theme in their keywords. This keyword will also be used to automatically create a list of available themes at https://typedoc.org/guides/themes/.
You don't have to create a npm package to use a custom theme. You can also specify TypeDoc's plugin option to load a local .js file.