Internal Program Version: libqt5-qtbase  5.15.18

The Qt 5 Core library. It adds these features to C++:

* a mechanism for object communication called signals and slots
* queryable and designable object properties
* hierarchical and queryable object trees that organize
* object ownership in a natural way with guarded pointers (QPointer)
* a dynamic cast that works across library boundaries

https://www.qt.io