This qt5 platformtheme uses the GTK3 file dialogs, reads some GNOME settings, draws an Adwaita style Wayland decoration, prefers Adwaita theme, etc.
Git master is used for qt 5.15 compatibility.
Created attachment 216888 [details]
A commit references this bug:
Date: Thu Dec 17 21:24:04 UTC 2020
New revision: 558334
Add new port x11-themes/qgnomeplatform:
Qt 5 Platform Theme designed to fit into GNOME.
Submitted by: Greg V
I added this port under x11-themes, where other Qt styles live. Thanks!