@GinoMan2440 said:
However for any other libraries, you have to add the library just to that specific project, instead of for example just being able to reference it by typing...
Your libraries (or more correctly headers) are not in system-wide recognized location.
Question: How can I make the headers for the library globally available to Qt so that it suggests the headers and suggests the types and symbols of that header in their proper contexts like it does for the STL, OpenGL, and the Windows SDK as well as pass those headers to the compiler so that the compiler knows where they are?
You can create a feature for qmake, where you add the paths to the headers and the binaries. You can use my repo where I've susbstituted the compilers as a template. The .prf file you copy in $QTDIR/mkspecs/features and you can use it with the CONFIG variable in your project, like this:
CONFIG += my_cool_curl_feature
Kind regards.