gInterpreter->GetClassSharedLibs often doesn't give an answer.

For the doxygen job, the list of used libraries is generated using

gInterpreter->GetClassSharedLibs("TNamed");

For many classes, this returns `nullptr`, e.g. TNamed.

For some, however, it works. But it's not because they are in a rootmap, e.g. `RooGaussian`:

root [0] gInterpreter->GetClassSharedLibs("RooGaussian")

(const char *) "libRooFit.so"

Also, at least in the working examples I found, it doesn't do what the documentation promises. It only returns the first library, but not the library this one depends on. See the example above. The doc is here:
https://root.cern/doc/master/classTCling.html#af089893320ff2df9bf53f24acaef039b