In the case of gsignalconnect it is a macro around gsignalconnectdata. Many functions are actually c macros and are unavailable in the introspection files. There are other, stand alone projects in various state of maintenance, like Caribou. 19 GTK 3 versions have already been developed for the following components: LXAppearance, LXAppearance-ObConf, LXDE-common, LXDE-icon-theme, LXDM, LXhotkey, LXInput, LXLauncher, LXPanel, LXRandR, LXSession, LXTask, LXTerminal, Openbox. GNOME Shell, for instance, uses IBus for its own on screen keyboard. GTK 3 port As of May 2020, there is an experimental GTK 3 port developed by the Arch Linux community. Some functions are missing like gsignalconnect. GTK provides extension points for input method modules, like IBus, to be able to insert text into the various text entry widgets.