Debug assertion in CFrame::CollectInvalidRects::addRect()

Hi Arne,

that was already very helpful. Unfortunately, I’m in an environment where the fact that UI-Updates are potentially and implicitly triggered from other threads is a given. I’m pretty confident though that using setDirty() in those cases helped to tackle the reported issue. invalid() can still be used in other cases where it’s obvious that they are coming from the main thread. Overlapping views aren’t an issue for us anyway. Thanks again!