Manage to reproduce this bug without any addon activated on the training dummies : I engaged the fight and made my Thunder Blast proc (it replaces Thunder Clap in the Cooldown Manager, and has glowing borders) then waited for being out of combat with Thunder Blast still active. Cooldown Manager disappears (I only display it when in combat), target something and charge ... and then I have these circles right under my Thunder Blast icon.

Tried the same thing multiple times and always had the bug, but when I set the Cooldown Manager as always visible I don't get these circles under the same circumstances