Just a info block for those daring to build the latest openmsx debugger master from source on Ubuntu 20.04 or variants (kubuntu in my case). It seems somewhere along the line Qt5 changed some rules and openmsx debugger will not build using the default development packages as supplied by the default repositories. After some fiddling around in endless circles I got the fix for a working build without having to do all kinds of modifications to the system (and bother the makers):
Changed all Qt::SkipEmptyParts to QString::SplitBehavior::SkipEmptyParts in DebuggerForm.cpp (2 changes total)
Changed all Qt::KeepEmptyParts to QString::SplitBehavior::KeepEmptyParts in Symboltable.cpp (1 change total)
I am not sure about this but the changes are required because these symbols are deemed outdated in Qt5.