The tab bars in the Rachni theme had an issue related to an attempted
property of qproperty-drawBase: 0 in the .qss file. This, in theory,
should have worked and removed the base of the tab bar, but there is a
bug that prevents this from consistently applying, as detailed here:
https://bugreports.qt.io/browse/QTBUG-2982
This fix removes that property, and adjusts the styling of the tabs
themselves for a more consistent experience. Tabs should no longer be
cut off or displayed improperly.
In addition, this also corrects an issue with the scene/source rename
QLineEdit field displaying improperly.
c3badc4a54