It seems to be caused when the game has to load in a bunch of graphics, for example entering Dornogal, or simply just opening the backpack or the appearance collection, but what keeps happening fairly often in the past 2 weeks is that the game freezes for a little while. This can be anywhere between 3 and 15 seconds, and usually you can’t move or interact with the UI in the meantime, and even more graphics unload (like your character).
It ranges between really annoying and a big problem.
Is Blizzard aware? Are they working on it? Is there any fix/workaround in the meantime?