All of a sudden: System coming apart at the seams...

[sumski]

I have almost the same output, but lancelot is not crashing:

...
QSqlDatabasePrivate::removeDatabase: connection 'qt_sql_default_connection' is still in use, all queries will cease to work.
QSqlDatabasePrivate::addDatabase: duplicate connection name 'qt_sql_default_connection', old connection removed.
I/O warning : failed to load external entity "/usr/share/qalculate/prefixes.xml"
I/O warning : failed to load external entity "/usr/share/qalculate/currencies.xml"
I/O warning : failed to load external entity "/usr/share/qalculate/units.xml"
I/O warning : failed to load external entity "/usr/share/qalculate/functions.xml"
I/O warning : failed to load external entity "/usr/share/qalculate/datasets.xml"
I/O warning : failed to load external entity "/usr/share/qalculate/variables.xml"
I/O warning : failed to load external entity "/usr/share/qalculate/currencies.xml"
I/O warning : failed to load external entity "/home/hrvoje/.qalculate/eurofxref-daily.xml"
I/O warning : failed to load external entity "/home/hrvoje/.qalculate/eurofxref-daily.xml"
lancelot(16256)/libplasma Plasma::Package::isValid: Could not find required file mainscript

Try enabling kdebugdialog, and see if there's any interesting output

[oshunluvr]

I gave up and renamed .kde which fixed the crash. I woke up early this morning so the hour or so to reset everything is spent. Weird that it sort of happened out of the blue, though.