As for your examples, Konqueror and Falkon might be blocked because they use Qt WebEngine – which embeds Blink in the Qt framework [0].
[0]: https://en.wikipedia.org/wiki/Blink_(browser_engine)#Framewo...
In this case it's blocking the embedded Blink, which is their browser engine, so at least they're consistent?
Blink forked from Webkit, which started as a fork of the KHTML and KJS libraries from KDE. Many KDE-projects are built upon Qt, but Qt is an independent project.