It does, called "Views". There's some documentation on it in the Chromium codebase. https://chromium.googlesource.com/chromium/src/+/master/docs...

I've used CEF to embed Chromium in Qt without too much difficulty. I made a C++ poc [0] and toyed with a Rust one a while back [1].

0 - https://github.com/cretz/qt_cef_poc 1 - https://github.com/cretz/rust-qt_cef_poc

I can't remember if it's the same with chrome, but firefox actually uses its rendering engine to render the window chrome as well.