Accurate C++ IntelliSense requires access to the C++ headers that are referenced by C++ source files. For Linux scenarios the headers referenced by a Linux MSBuild or CMake project are copied to Windows by Visual Studio from the Linux device (or VM, or Docker container, or WSL system) being targeted for the build. Visual Studio then uses these headers to provide IntelliSense. If the headers are not the correct versions, for example they are gcc headers rather than clang headers, or C++11 headers rather than C++17 headers, then the IntelliSense may be incorrect, which can be very confusing to the user. Also, for some scenarios the number of headers can be very large and so the copy can take a long time. Visual Studio 2019 version 16.5 Preview 1 improves both the accuracy and the performance of the header copy, providing better IntelliSense for Linux projects.