I've been getting for some time an occasional rather annoying flicker onscreen in Explorer 11 that only appears when trickle is enabled and where there are components using opacity.
It seems to occur mostly when trickling to blocks that contain static components like Graphic or Text on a page that also includes a component such as Tabs or a quiz with the Tutor feedback overlay. Without these the trickling runs smooth.
Thought it was my theme but I've reproduced the issue using the latest Vanilla theme and Box menu in the latest AT. Any ideas what this might be?