matugen: make GTK4 live-refresh opt-in, off by default. Bump the settle

timeout
fixes #2552

core/internal/matugen/matugen.go

@@ -928,7 +928,14 @@ func expectColorSchemeEcho(scheme string) {
 	}
 }
 
+// The color-scheme round trip is the only mechanism that makes running GTK4
+// apps reload ~/.config/gtk-4.0 CSS (a gtk-theme flip does not). But apps
+// following the portal color-scheme (Chromium) can drop the restore signal
+// mid-repaint and latch the wrong mode, so this is opt-in.
 func refreshGTK4() {
+	if os.Getenv("DMS_ENABLE_GTK4_REFRESH") != "1" {
+		return
+	}
 	output, err := utils.GsettingsGet("org.gnome.desktop.interface", "color-scheme")
 	if err != nil {
 		return
@@ -947,7 +954,7 @@ func refreshGTK4() {
 		log.Warnf("Failed to toggle color-scheme for GTK4 refresh: %v", err)
 		return
 	}
-	time.Sleep(50 * time.Millisecond)
+	time.Sleep(400 * time.Millisecond)
 	expectColorSchemeEcho(current)
 	if err := utils.GsettingsSet("org.gnome.desktop.interface", "color-scheme", current); err != nil {
 		log.Warnf("Failed to restore color-scheme for GTK4 refresh: %v", err)

quickshell/Services/PortalService.qml

@@ -97,7 +97,7 @@ Singleton {
         return typeof Theme !== "undefined";
     }
 
-    // Only follow values stable for the settle window — the GTK4-refresh toggle reverts within ~50ms and following it would loop.
+    // Only follow values stable for the settle window — the opt-in GTK4-refresh toggle reverts within ~400ms and following it would loop.
     function evaluateColorScheme() {
         if (!canSyncColorScheme())
             return;
@@ -111,7 +111,7 @@ Singleton {
 
     Timer {
         id: colorSchemeSettleTimer
-        interval: 750
+        interval: 1000
         onTriggered: {
             if (!root.canSyncColorScheme())
                 return;

quickshell/matugen/gtk3-assets/README.md

@@ -0,0 +1,10 @@
+# adw-gtk3 assets
+
+Image assets vendored from [adw-gtk3](https://github.com/lassekongo83/adw-gtk3)
+(`src/assets/`), used by the generated GTK3 light theme
+(`quickshell/matugen/templates/gtk-light-colors.css`, itself derived from
+adw-gtk3's `gtk.css`).
+
+adw-gtk3 is licensed under the GNU Lesser General Public License v2.1 — see
+`LICENSE.adw-gtk3`. These files are covered by that license; the rest of this
+repository remains under its own license.