I am tanking on my protection paladin for mythic pluses. I have the talent “Final Stand” which is supposed to get me to keep aggro when I use Divine Shield. Most of the time it works. However, sometimes when I use bubble, the enemy drops aggro on me and attacks another player. This is especially noticeable on certain boss fights such as Treemouth in Brackenhide Hollow when he casts Consume. Even if I cast my taunt (Hand of Reckoning), and even though the boss nameplate is fully red to indicate full aggro, he will ignore me for a good 5-10 seconds. I think I had to taunt 3 times before he finally came after me. Meanwhile, he was doing the tankbuster and melee-ing some poor dps in the group. Another example is on the boss Decatriarch Wratheye (same dungeon), where she started attacking another player even though it showed me as having full aggro still. This again lasted about 5-10 seconds.
I believe this is a bug. If we select “Final Stand” then we should NEVER lose aggro after bubbling, nor should our regular taunt not work on the boss during bubble.