Several programs have a daemon mode call gtk_init() before fork()ing. This is unsafe, and when it goes wrong this will typically manifest as the daemon hanging shortly after forking, and appearing to simply do nothing at all. Please check this bug is not affecting PolicyKit.
Thanks for your report. The string gtk_init does not appear in polkit codebase.
Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.