Clientlibs allow you to extend the default implementation to realize new functionality, while reusing the standard functions, objects, and methods. When customizing, you can create your own clientlib under/apps.The new clientlib must:
depend on the authoring clientlibcq.authoring.editor.sites.page
be part of the appropriatecq.authoring.editor.sites.page.hookcategory
I have tried above as well, but don't see the dropdown for custom extension.
Even ACS commons has an extension audio asset finder. When I install the package, I don't see it in Asset finder drop down