Currently, VE waits with initialization until site and user js has been loaded and executed (function getTarget in ve.init.mw.DesktipArticleTarget.init.js), but not for the global.js from Extension:GlobalCssJs.
Waiting for these modules is necessary to make it possible to define plugins: When VE starts right away (because you opened the page in a new tab, or edited from a non-standard view) these modules only load after VE has started initialization. This currently means that plugins defined in global.js may be missing, because their definition comes too late.