Oh loggin on, I can see the following error:

Interface\AddOns\Dominos_Buff\main.lua:261: attempt to call global 'GetSpellName' (a nil value)
Count: 99

Call Stack:
[C]: in function GetSpellName' Interface\AddOns\Dominos_Buff\main.lua:261: in function <Interface\AddOns\Dominos_Buff\main.lua:254> Interface\AddOns\Dominos_Buff\main.lua:280: in function <Interface\AddOns\Dominos_Buff\main.lua:279> [C]: in functionActionButton_Update'
Interface\FrameXML\ActionButton.lua:436: in function `ActionButton_OnEvent'
[string ":OnEvent"]:1: in function <[string ":OnEvent"]:1>

Dominos_Buff was discontinued over a year ago, use Inline Aura instead.

Must be the remains of an old installation.
Thanks for the quick answer and just keep up the
great work!