Why does <port> not work after integrating vcpkg within VS ? (includes not found)

[Neumann-A]

Failure:
# include <someheader.h(pp)?> does not work out of the box after integration

Reason:
The vcpkg integration just adds <vcpkg_installed_dir>/include to the header search list. If a port has a more complex or versioned include folder structure this is commonly not enough for finding the headers. Since VS has no build-in search for headers/libraries, it cannot correctly add this additional include folders.

Solution:
Add $(_ZVcpkgCurrentInstalledDir)include/<subfolder> (sometimes also $(_ZVcpkgCurrentInstalledDir)lib/include/<subfolder>) to your additional include folders or switch from VS to CMake (or Meson but that is more complicated to setup).

affected ports (I know of):
Qt
VTK
glib(mm), gtk(mm)

Issues with this problem:
#20041
#20007
#18760
#18328
#17702
#16970

(Please feel free to extend the list in a comment.)