As of May 2020, there is an experimental GTK 3 port developed by the Arch Linux community. 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, PCManFM. One advantage of using GTK 3 is that GTK 3 programs run natively on Wayland. PCManFM is a popular file manager for use with tiling window managers and hence, having a Wayland-native PCManFM is useful for people that use Sway.
Availability