Mangle Not Learned on Speccing into Feral Combat

WoW Classic WoW Classic Bug Report
1

Cataclysm Classic.

Mangle not learnt upon speccing into Feral Combat

2

The only way I was able to get it to re-appear was respeccing BOTH talent specs (dual talent specs) and then leaving at least 1 point unspent in BOTH talent specs.