i: /.mozconfig
o: /.mozconfig

+ac_add_options --target=x86_64-w64-mingw32
+ac_add_options --enable-application=browser
+ac_add_options --enable-default-toolkit=cairo-windows
+ac_add_options --disable-debug
+ac_add_options --enable-optimize
+ac_add_options --disable-crashreporter
+ac_add_options --disable-updater

+ac_add_options --without-toolchain-prefix
+ac_add_options --disable-stdcxx-compat
+ac_add_options --without-wasm-sandboxed-libraries
+ac_add_options --disable-bootstrap

+ac_add_options --enable-compile-environment
+ac_add_options --with-toolchain-prefix=/usr/bin/x86_64-w64-mingw32-

+mk_add_options AUTOCLOBBER=1
+export MOZ_DISABLE_SHADER_COMPILATION=1

+# These override Clang
+unset CC
+unset CXX
+export CC=x86_64-w64-mingw32-gcc
+export CXX=x86_64-w64-mingw32-g++