allow fury and arms warriors to use glyph of thunder strike (thunder clap) which adds some lightning strikes to thunder clap.
they randomly broke it in the pre patch of dragonflight and have ignored bug reports about it since. i myself have sent in 2 in game and made 2 seperate threads about it.
its a fix that could be done while eating your breakfast and drinking your coffee with your eyes still half asleep.
back in Dragonflight it was largely unnoticable until they made the entire Arms set bonus in one of the raids center around Thunder Clap, then immediately it was obvious it wasn’t working.
now in TWW its even more funny - fury’s secondary hero talent tree (that no one uses because its 15% behind slayer) is built around thunder clap, yet Glyph of Thunder Strike is ‘invalid’ for Fury Specialisation.
heres my thread about it at TWW launch:
and heres my thread about it in the middle of Dragonflight: