Thank you for reminding us @Andy.
We will look into it. Although, VS Code does not allow extensions to access files outside the workspace (we would have to work-around it and it would only work on some systems)
The recommended solution is to
Add Folder to Workspace. The IntelliSense should then parse the content of it as well.
Anyways; something like
includepath setting would be better I guess - we'll try to implement this as well.