SWT min Gtk version is going to be bumped again this release (to require Gtk 3.20+). All non EOLed Linux distributions are already at Gtk 3.24.
We plan to bump Gtk requirement to 3.24 for September release too.
This is important step so SWT work on GTK4 can be started now and thus the needs of it being expressed to GTK devs on time so we don't end in the GTK3 situation when porting SWT to it was started only after GTK 3.0 was final thus leading to many hacks.
Red Hat Eclipse Team