vscode natvis using launch configuration

Question

I am trying to debug a ROS2 node which uses Eigen matrices. I followed https://gist.github.com/JADC362/a4425c2d05cdaadaaa71b697b674425f.

However, to visualize Eigen matrices, I encountered natvis files. I never worked with them but I found a natvis file for the Eigen Library (https://github.com/cdcseacave/Visual-Studio-Visualizers/blob/master/Eigen.natvis)

My question now is how do I incorporate it in the launch file via

{
   "name": "C++ Debugger",
   "request": "launch",
   "type": "cppdbg",
   "miDebuggerServerAddress": "localhost:3000",
   "cwd": "/",
   "program": "[build-path-executable]"
   "visualizerFile": "${workspaceFolder}/Visual-Studio-Visualizers/Eigen.natvis",
}

But I can't really see any changes during debugging. I hoped t be able to examine the matrices now....

Any ideas?

Max