fix(prefs): disconnect page settings listeners on destroy

The General and Keyboard Shortcuts pages never disconnected their
settings listeners. The preferences process outlives its window, so a
later settings change ran the handlers on disposed widgets. The
Maximizing page's disconnect-on-destroy pattern moves to
pageListener() in prefs/rows.js and is used by all three pages.

Author: KonstantinMerkel

prefs/general.js

@@ -3,10 +3,12 @@ import Gio from 'gi://Gio';
 import GLib from 'gi://GLib';
 import Gtk from 'gi://Gtk';
 import { Logger } from '../lib/utils/logger.js';
+import { pageListener } from './rows.js';
 
 /** Preferences page for gaps and debugging. */
 export function buildGeneralPage(settings) {
     const page = new Adw.PreferencesPage({ title: 'General', icon_name: 'preferences-system-symbolic' });
+    const listen = pageListener(page, settings);
 
     // --- Gaps Group ---
     const gapsGroup = new Adw.PreferencesGroup({ title: 'Gaps' });
@@ -33,7 +35,7 @@ export function buildGeneralPage(settings) {
         innerGapsRow.visible = enabled;
         outerGapsRow.visible = enabled;
     };
-    settings.connect('changed::enable-gaps', updateGapsVisibility);
+    listen('changed::enable-gaps', updateGapsVisibility);
     updateGapsVisibility();
 
     page.add(gapsGroup);

prefs/maximize.js

@@ -2,7 +2,7 @@ import Adw from 'gi://Adw';
 import Gio from 'gi://Gio';
 import Gtk from 'gi://Gtk';
 import { appEntry, withEntry } from '../lib/domain/policies/override/self-maximize.js';
-import { choiceRow } from './rows.js';
+import { choiceRow, pageListener } from './rows.js';
 
 const SELF_MAXIMIZE_MODES = [
     { value: 'never', label: 'Never', subtitle: 'Tiled windows maximize only through the shortcuts' },
@@ -107,9 +107,7 @@ function pickApp(parent, apps, onPicked) {
 /** Preferences page for maximize and fullscreen behaviour of tiled windows. */
 export function buildMaximizePage(settings) {
     const page = new Adw.PreferencesPage({ title: 'Maximizing', icon_name: 'view-fullscreen-symbolic' });
-    const signalIds = [];
-    const listen = (signal, callback) => signalIds.push(settings.connect(signal, callback));
-    page.connect('destroy', () => signalIds.splice(0).forEach((id) => settings.disconnect(id)));
+    const listen = pageListener(page, settings);
     let cachedApps = null;
     const apps = () => (cachedApps ??= installedApps());
 

prefs/rows.js

@@ -1,6 +1,17 @@
 import Adw from 'gi://Adw';
 import Gtk from 'gi://Gtk';
 
+/**
+ * Settings listener tied to a page: everything connected through it is disconnected when the page is destroyed, so
+ * handlers never run on the widgets of a closed preferences window.
+ * @returns {(signal: string, callback: Function) => void}
+ */
+export function pageListener(page, settings) {
+    const signalIds = [];
+    page.connect('destroy', () => signalIds.splice(0).forEach((id) => settings.disconnect(id)));
+    return (signal, callback) => signalIds.push(settings.connect(signal, callback));
+}
+
 /** Combo row storing one of `choices` in a string key; the subtitle explains the current choice. */
 export function choiceRow(settings, key, title, choices) {
     const row = new Adw.ComboRow({ title, model: Gtk.StringList.new(choices.map((c) => c.label)) });

prefs/shortcuts.js

@@ -4,6 +4,7 @@ import Gio from 'gi://Gio';
 import GObject from 'gi://GObject';
 import Gtk from 'gi://Gtk';
 import { Logger } from '../lib/utils/logger.js';
+import { pageListener } from './rows.js';
 
 const ShortcutRowMixin = {
     _recordShortcut() {
@@ -145,6 +146,7 @@ export function buildShortcutsPage(settings) {
         title: 'Keyboard Shortcuts',
         icon_name: 'input-keyboard-symbolic',
     });
+    const listen = pageListener(shortcutsPage, settings);
 
     const wmSettings = new Gio.Settings({ schema_id: 'org.gnome.desktop.wm.keybindings' });
     const allRows = [];
@@ -237,7 +239,7 @@ export function buildShortcutsPage(settings) {
         const showCustom = mode === 'custom';
         focusRows.forEach((r) => (r.visible = showCustom));
     };
-    settings.connect('changed::focus-window-mode', () => {
+    listen('changed::focus-window-mode', () => {
         updateFocusVisibility();
         updateConflicts();
     });
@@ -275,7 +277,7 @@ export function buildShortcutsPage(settings) {
         const showCustom = mode === 'custom';
         moveRows.forEach((r) => (r.visible = showCustom));
     };
-    settings.connect('changed::keybindings-mode', () => {
+    listen('changed::keybindings-mode', () => {
         updateVisibility();
         updateConflicts();
     });
@@ -314,7 +316,7 @@ export function buildShortcutsPage(settings) {
         const strv = settings.get_strv('shortcut-close-monitor');
         closeMinRow.visible = strv.length > 0 && strv[0] !== '';
     };
-    settings.connect('changed::shortcut-close-monitor', updateCloseMinRowVisibility);
+    listen('changed::shortcut-close-monitor', updateCloseMinRowVisibility);
     updateCloseMinRowVisibility();
     monitorGroup.add(closeMinRow);
 

tests/prefs.test.js

@@ -419,6 +419,21 @@ describe('WorkflowTilingPreferences', () => {
         });
     });
 
+    it('disconnects the General and Keyboard Shortcuts listeners when their pages are destroyed', () => {
+        prefs.fillPreferencesWindow(mockWindow);
+        const listeners = (key) => (mockListeners[`changed::${key}`] ?? []).length;
+        // a ShortcutRow keeps its own listener on its key; it is released in vfunc_dispose
+        const closeMonitorListeners = listeners('shortcut-close-monitor');
+
+        addedPages.find(p => p.title === 'General').emit('destroy');
+        addedPages.find(p => p.title === 'Keyboard Shortcuts').emit('destroy');
+
+        expect(listeners('enable-gaps')).toBe(0);
+        expect(listeners('focus-window-mode')).toBe(0);
+        expect(listeners('keybindings-mode')).toBe(0);
+        expect(listeners('shortcut-close-monitor')).toBe(closeMonitorListeners - 1);
+    });
+
     it('should store the monitor change policy chosen on the Monitors page', () => {
         mockSettingsStore['hotplug-policy'] = 'follow-primary';
         prefs.fillPreferencesWindow(mockWindow);