Shows a circle around your cursor while global cooldown is refreshing!
You need to set a spell to track in the options menu.

There's another spark indicating casttime.
It starts out green and turns red, when (casttime - latency) is over (similar to quartz latency).

Additionaly it can show icons around the circle to show cooldowns of spells like
Wild Growth, Swiftmend, Holy Shock etc. Currently only Druids, Paladins and Priests are implemented.

If you find a bug or have any wishes for the addon feel free to write a ticket.

Keep in mind that a lot of addons mess with the default castbar.
Should the toggle for it not work properly its most likely that another addon hides it as well.

To open the options menu type "/gcd"

Here is a screenshot with all features enabled:

Stuff I have in mind:

• More options for textures (width, height, etc.)
• Make the spark radius adjustable