I recently posted a question about how to track clicks on "Share" button. I closed it because at the time it seemed it was impossible.

However, afterwards I did some digging and it seems it is possible with Google Tag manager: https://pathfinderseo.com/blog/track-a-button-click/

I know Tiger Skin has a setting for Google Analytics where you can put Google property ID. However, Google Tag Manager is separate.

Is there a documentation about how to integrate Google Tag Manager with Tiger skin? I think "Advanced/Custom code/JavaScript" could be the right place but I am not sure - I am not a front end developer.

Tiger already loads the Google tag manager script - see Tiger > Advanced > Site admin > Google Analytics. For Version, choose Global Site Tag, and enter your property ID.

The rest of the setup for click tracking is done entirely on the Google Analytics site. There is no other code required on the album page, so there's nothing more that jAlbum or Tiger can do.