# XPCOMUtils module XPCOMUtils is a utility class that lives in {searchfox}`resource://gre/modules/XPCOMUtils.sys.mjs `. Its name is a little confusing because it does not live in XPCOM itself, but it provides utilities that help JS consumers to make consuming `sys.mjs` modules and XPCOM services/interfaces more ergonomic. ```{js:autoclass} XPCOMUtils :members: ```