P2: Important Description
When using a webview inside of a scrollbar area, I found a fairly repeatable error where the right hand side produces single-pixel-width black lines at particular window widths. This happens very often when resizing the window, but in particular circumstances is still happening when the window is static. In the attached image, the black line on the right should not be present, and generically isn't for most window widths.
Attached is a roughly minimal example, which produces the error on startup. The text width of the label seems important for producing the effect reliably.
Less reliably, in some circumstances the central webview widget is completely black. I have had this happen a couple of times while loading the attached example, but haven't figured out how to reproduce it.
