TrinityCore/TrinityCore — comment on commit 4b0acb743264971859a7c26684394792706f5209
File:  line 0
By Aokromes:

Reading wowhead this is incorrect.

I've never been able to eat/drink while invisible on boss fights. It gives me the error message saying I'm still in combat. However if the group wipes, I don't get boss aggro when I'm invisible and I can survive. I haven't tested it on non-boss encounters (mainly because I don't go OOM on trash pulls,) so I don't know if you can go invisible and eat/drink then.