Easy to reproduce, albeit expensive.
The Bug: If you socket a gem into the additional bracer slot granted by being a blacksmith, and then drop the profession, the color of the additional gem that is socketed “counts” towards the UI showing your meta gem being active.
I have a yellow gem in my additional Blacksmithing socket on my bracers. I am no longer a blacksmith and have no yellow gems in any other slot, and I also do not have the enchanted tear in any other slot. My meta gem calls for a yellow gem to be active, when I hover over my helm in the character pane the UI element shows that my Meta Gem appears to be active and the yellow gem condition is satisfied. If I look at my stats, I am not benefiting from the meta gem as it is in fact not active, as it shouldn’t be since I don’t have a yellow gem in an active gem slot.
So while the meta gem benefits are not being applied to my character, the UI indicates that it active. While it may be a niche case, I spent 3 weeks raiding without my 3% crit, and I am sure I am not the only one out there. Also the WA I tested also thinks my Meta is active when it is not.