AoE Skills like skyfire or glare ice leave an graphic display on the ground. Works fine for even ground.
As soon as the ground is uneven, for example on stairs or whatever, on the one side where the stairs go up the graphic goes inside the ground and on the other side where the stairs go down the graphic "floats" over the ground, since the graphic only grows horizontally from it's source. The effect (damage, whatever, ...) though is still applied in the whole radius. Quite annoying when you cannot properly see where the radius starts or ends.
Not as much annoying but still annoying is the other side, when the "floating" effect blocks your view.

Example from today on Alchemists' Citadel: The fire witch stood under the platform where the crank for the last checkpoint is on top. She shot the skyfire from below at the bottom side of the platform so there was no graphic display visible on the top side but the damage got through and killed everyone. Nobody knew where to run since nobody saw the radius.

On what graphics setting are you playing?

if you are playing on high quality you should not see this.

if you play in 90's, Max Performance and High Performance then what you are dicribing has always been like that for as far as I know.

Sorry, forgot to mention my graphics setting. I'm playing with the 90's settings.
I will try out high quality. Do you know which of the settings is/are responsible for this graphic effects so I can only change the one(s)? Don't know if my computer can handle high quality on all settings. Would be nice if not only the best CPU owners can benefit from the correct graphic display.