[BUG] Elemental Mastery not properly displaying cooldown

[Panthyren]

1. Current Behavior

1.1. Description

Sometimes when you use elemental mastery after the 15s of the buff expires the icon displays it as available but obviously it won't trigger until it is actually off cooldown again.

1.2. How to Reproduce

      {Describe the steps to reproduce the particular bug, in detail:
       1. Wait for elemental mastery to come off cooldown
       2. Use elemental mastery
       3. Look at your action bar/WA after buff has expired and see that it still shows as available

1.3 Source Material

These are 10 short clips from the past week on my Elemental Shaman https://youtu.be/kc_s5bzk1pI https://youtu.be/r7uRY61XriE https://youtu.be/m3SZgXxpUeE https://youtu.be/2g9TNWPEYC4 https://youtu.be/8ZXBEMgmLSA https://youtu.be/swYBcObaNsU https://youtu.be/afcFgqXfs00 https://youtu.be/JPUeoeMWXmo https://youtu.be/Fir2Z-xkwRk https://youtu.be/kkWu5Odb-sk

This is a convo from one of the ele shaman disc mods talking to Zirene about it from around ICC launch. https://x.com/LionButLeon/status/1717329758847943064

2. Expected Behavior

2.1. Description

After Elemental Mastery comes of cooldown and is used rather than display it as available it should show that it is on cooldown.

2.2 Source Material

{Video, Posts, etc..}

[Artemishowl]

Valid issue, ticketing

[kayla-glick]

I've received a report that this is also happening in SoD, so presumably in era as well. That also lines up with this Reddit post from Classic 2019 mentioning the issue back then