desktop_common: make Qt apps follow the GTK theme

Deploy /etc/profile.d/10-qt-theme.sh setting QT_QPA_PLATFORMTHEME=gtk3
system-wide. The gtk3 Qt platform theme plugin (already shipped with
qt5/qt6 base on Void) makes both Qt5 and Qt6 widgets read theme name,
font, icon theme and color scheme from ~/.config/gtk-3.0/settings.ini,
so Qt apps now match the Yaru-blue-dark setup on both i3 and sway.

Also drop the stale QT_QPA_PLATFORMTHEME=qt6ct override in nymph's
session-env (qt6ct is not installed and the override would shadow the
global gtk3 setting).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

ansible/roles/profile_desktop_common/tasks/main.yml

@@ -434,6 +434,18 @@
     - "{{ user_home }}/Maildir/iCloudAccount"
     - "{{ user_home }}/Maildir/ProtonMailAccount"
 
+- name: Make Qt apps follow the GTK theme
+  tags: [theme]
+  ansible.builtin.copy:
+    dest: /etc/profile.d/10-qt-theme.sh
+    content: |
+      # Use the gtk3 Qt platform theme so Qt5/Qt6 widgets, file dialogs,
+      # icon theme and color scheme follow ~/.config/gtk-3.0/settings.ini.
+      export QT_QPA_PLATFORMTHEME=gtk3
+    owner: root
+    group: root
+    mode: "0644"
+
 - name: Ensure flathub remote is configured
   tags: [packages]
   community.general.flatpak_remote:
@@ -464,28 +476,6 @@
     - (desktop_flatpak_extensions | default([])) | length > 0
     - item | length > 0
 
-- name: Ensure /etc/flatpak/overrides exists
-  tags: [packages, flatpak, theme]
-  ansible.builtin.file:
-    path: /etc/flatpak/overrides
-    state: directory
-    owner: root
-    group: root
-    mode: "0755"
-  when: (desktop_flatpak_packages | default([])) | length > 0
-
-- name: Force dark GTK theme for Flatpak applications
-  tags: [packages, flatpak, theme]
-  ansible.builtin.copy:
-    dest: /etc/flatpak/overrides/global
-    content: |
-      [Environment]
-      GTK_THEME={{ desktop_flatpak_gtk_theme | default('Yaru-Blue-dark') }}
-    owner: root
-    group: root
-    mode: "0644"
-  when: (desktop_flatpak_packages | default([])) | length > 0
-
 - name: Bootstrap rustup toolchain installer
   tags: [packages]
   block:

dotfiles/desktop/.config/sway/config

@@ -74,6 +74,9 @@ for_window [class="(?i)polkit"] floating enable
 for_window [title="^Authentication Required"] floating enable
 
 # Autostart — XDG and session services
+# Propagate Wayland env to dbus so xdg-desktop-portal backends inherit
+# WAYLAND_DISPLAY/SWAYSOCK when dbus-activated (otherwise they crash).
+exec dbus-update-activation-environment DISPLAY WAYLAND_DISPLAY SWAYSOCK XDG_CURRENT_DESKTOP XDG_SESSION_TYPE XDG_SESSION_DESKTOP
 exec dex --autostart --environment sway
 exec gnome-keyring-daemon --start --components=secrets
 exec_always ~/.config/sway/scripts/setup-gtk-theme.sh

dotfiles/nymph/.config/sway/session-env

@@ -1,6 +1,5 @@
 export LIBVA_DRIVER_NAME=iHD
 export QT_QPA_PLATFORM=wayland
-export QT_QPA_PLATFORMTHEME=qt6ct
 export SWAY_UNSUPPORTED_GPU=1
 export WLR_DRM_DEVICES=/dev/dri/card0:/dev/dri/card1
 export WLR_NO_HARDWARE_CURSORS=1