/usr/ is in libjavascriptcoregtk-4.0-dev 2.18.6-1~deb9u1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/
/usr/share/doc/
/usr/include/
/usr/include/webkitgtk-4.0/
/usr/include/webkitgtk-4.0/JavaScriptCore/
/usr/include/webkitgtk-4.0/JavaScriptCore/JSBase.h
/usr/include/webkitgtk-4.0/JavaScriptCore/JSContextRef.h
/usr/include/webkitgtk-4.0/JavaScriptCore/JSObjectRef.h
/usr/include/webkitgtk-4.0/JavaScriptCore/JSStringRef.h
/usr/include/webkitgtk-4.0/JavaScriptCore/JSTypedArray.h
/usr/include/webkitgtk-4.0/JavaScriptCore/JSValueRef.h
/usr/include/webkitgtk-4.0/JavaScriptCore/JavaScript.h
/usr/include/webkitgtk-4.0/JavaScriptCore/WebKitAvailability.h
/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/pkgconfig/
/usr/lib/x86_64-linux-gnu/pkgconfig/javascriptcoregtk-4.0.pc
/usr/share/doc/libjavascriptcoregtk-4.0-dev/
/usr/share/doc/libjavascriptcoregtk-4.0-dev/NEWS.Debian.gz
/usr/share/doc/libjavascriptcoregtk-4.0-dev/changelog.Debian.gz
/usr/share/doc/libjavascriptcoregtk-4.0-dev/changelog.gz
/usr/share/doc/libjavascriptcoregtk-4.0-dev/copyright
/usr/share/gir-1.0/
/usr/share/gir-1.0/JavaScriptCore-4.0.gir
/usr/share/lintian/
/usr/share/lintian/overrides/
/usr/share/lintian/overrides/libjavascriptcoregtk-4.0-dev
/usr/lib/x86_64-linux-gnu/libjavascriptcoregtk-4.0.so