WKWebView constrains issue when keyboard pops up

Having the same issue. I'm running a clean project, vanilla setup and this issue comes up as soon as the webview keyboard gets focus. It seems to be a common issue, might just be a bug in iOS 11.

Also see:

WKWebView LayoutConstraints issue

My assumption is this a bug in ios 11. The complaints are about the components in the button bar for the keyboard which are all using default values set by the os. I have run the same code on both ios 9 and ios 10 and get no error messages.