We have been talking about adding possible QtWebEngine support for years now and it has just happened:
https://github.com/FreeCAD/FreeCAD/pull/1937
Likely it makes sense to mention that. Under i guess the general notes about the current state of porting to Python 3 and Qt 5 (or under Web Workbench). A note that porting to Python 3 and Qt 5 effort is considered done and mature. That will likely make sense too. At the end of the development cycle. As a month or two back, most developer already stated, they have moved to using Py3/Qt5 toolchain.