At the start of one of my turns in a BFZ story battle, I noticed this anomaly.
The green and white gems on the right clearly should have been cleared away.
I matched the Loyalty gems on my turn and the green and white gems then matched immediately (ie. before the green gem fell to form a 5)and were cleared.
I had the same thing happen on a match 3 blue so I tried to swap 2 of them and the swap was invalid cause one was actually green(changed to green after I tried to swap)
So the bug is probably a gem color display.
I pointed it out in another topic.
As you can see from my screenshot, matching the 3 Loyalty gems would not have cleared the white gems.
And the green gems would have cleared only after the Loyalty match.
Instead both were cleared at the same time as the Loyalty match.