It is hard to track all the changes under the hood when almost nothing makes it into the patch notes... but I think I saw something about better, consistent visibility of the red areas. No, it is not better, it is worse. Consistently - invisible. (Please note, to be specific: I am talking about the AoE effect, I think I saw all the targeting warnings, but what is left after - the deadly poison for example... has no indication.)
(And I think the same fix made the flame AoE in MSP deadly to touch once again... and with arguable "consistent" visibility as well.)
1