CEF

https://github.com/chromiumembedded/cef

Builds 4638 are taken from OBS project https://github.com/obsproject/cef
Builds taken from https://cef-builds.spotifycdn.com/index.html

Boost

https://www.boost.org/users/download/

Sourced from https://boostorg.jfrog.io/artifactory/main/release/1.67.0/source/boost_1_67_0.zip (or similar).
Prebuilt windows versions are produced by running the build with prebuilt boost disabled, and zipping the result.