Now that the 6.2.6 webengine is working ok-ish - I'm rebuilding the 6.2.8 code which is chromium 102.0.5005.177, using GCC 14. This is similar to the code in Qt 6.4.x.
As I recall, it compiled OK, but any use of javascript crashed the browser, we'll see what happens. Maybe a fresh review of the v8 code will highlight some problems <shrug>