It is a packaging problem. The .deb being created and installed on a bare Ubuntu install is missing something and it is something subtle like a dependency of a dependency of a dependency. Everything works perfectly in development on multiple development machines even when built on multiple versions of Ubuntu. The problem is in packaging this into a .deb which installs on machines that have zero network connection.
Boiling it down, there is a library or background/hidden executable used by WebEngine which isn't being packaged up and failed invocation of it does not log an error anywhere. Not to the terminal, syslog, no place I can find. If it would just stack dump or something it would be a 10 minute task to track down. Whatever this is has a "quietly hidden" failure and one doesn't see the result until that "main" module in webkit exits due to a missing connection number.
The self contained universe is both incomplete and ashamed of its inadequacies.
That's not good for a developer.
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