When linking object code that includes a custom subclass of QPlainTextEdit, I get the following error: undefined reference to `typeinfo for QPlainTextEdit'

I have been able to solve this problem by keeping more of the qt5_widgets symbols than those available in the depot API package, which are obtained from https://github.com/cproc/genode-symbols.

When looking at the symbols file, I see that the typeinfo and vtable symbols were manually added for some Qt5 widget classes. Given the commonly-used ability to inherit Qt5 classes, wouldn't it be best to keep these symbols for all classes? The classes with names that end in Private could be split into a separate API package for compatibility and/or to reduce the size of the symbols lists and the resulting .lib.so files.