LiNotify - Get Notified When A Chess Player Is Active
LiNotify is an extension that help you detect whether a chess player is online or playing at lichess.org.
If you visit the profile of a chess player on the server, you'll see a button that says 'Notify me', next to the list of recent games. Clicking it will trigger the application to notify you when the player is online.
LiNotify will also show you what status the user has, the most important one being 'playing', which means that the user is actively playing.
There are also options to disable the notifications for a user, or for all users. You can also turn off notifications for certain users.
