Qt upstram dropped webkit from their releases, and only provides "community releases" of webkit.
However, the webkit it uses is very outdated (538.1).
There are however active forks of Qt5 webkit, most prominently https://github.com/annulen/webkit .
This replaces www/qt5-webkit with that.
It is a drop in replacement, so everything should build fine against it.
Pro:
- Stuff works better
- Less outdated
Con:
- Fullscreen of youtube in qupzilla for example is broken