Not yet.
このスクリプトは単体で利用できません。右のようなメタデータを含むスクリプトから、ライブラリとして読み込まれます: // @require https://update.greatest.deepsurf.us/scripts/2599/16319/GM%202%20port%20-%20Function%20Override%20Helper.js
GreasyMonkey 2.x Beta will break lots scripts, this library has made to help function hooking.
It provides 2.x API exportFunction and cloneInto for 1.x support (Which is just dummy sandbox).
It's well documented(Should be..) in source.
Add unsafeExec, execute function as script text on page.
Fix this problem when hooking prototype / Object function.
return foo.apply({}, args); -> return foo.apply(this, args);
return bak.apply ({}, arguments); -> return bak.apply (this, arguments);
document.body -> document.head, to prevent document.body is null error.