Currently shadowmeld breaks upon starting a cast in all stages of the game.
It should only break at the end of casts.
The racial worked as such for the very large majority of retail vanilla. It changed in 1.10.
"Stealth and Invisibility effects will now be canceled at the beginning of an action (spellcast, ability use etc...), rather than at the completion of the action." patch 1.10
Currently shadowmeld breaks upon starting a cast in all stages of the game.
It should only break at the end of casts.
The racial worked as such for the very large majority of retail vanilla. It changed in 1.10.