diff --git a/Makefile b/Makefile
index 4e1aa28..2489034 100644
--- a/Makefile
+++ b/Makefile
@@ -72,7 +72,7 @@ pot:
 		--package-name="$(NAME)" \
 		--package-version="$(VERSION)" \
 		--output=./src/po/$(UUID).pot \
-		./src/*.js
+		./src/**/*.js
 	sed -i '1,4s/SOME DESCRIPTIVE TITLE./$(NAME)/g' ./src/po/$(UUID).pot
 	sed -i '1,4s/YEAR/$(COPYRIGHT_YEAR)/' ./src/po/$(UUID).pot
 	sed -i "1,4s/THE PACKAGE'S COPYRIGHT HOLDER/$(AUTHOR_NAME)/" ./src/po/$(UUID).pot
diff --git a/src/config.js b/src/config.js
index 3355ede..f860925 100644
--- a/src/config.js
+++ b/src/config.js
@@ -19,5 +19,8 @@ this program. If not, see <http s ://www.gnu.org/licenses/>.
 var EXT_NAME = 'Night Theme Switcher';
 var EXT_UUID = 'nightthemeswitcher@romainvigier.fr';
 
-var GSETTINGS_SCHEMA = 'org.gnome.desktop.interface';
-var GSETTINGS_PROPERTY = 'gtk-theme';
+var THEME_GSETTINGS_SCHEMA = 'org.gnome.desktop.interface';
+var THEME_GSETTINGS_PROPERTY = 'gtk-theme';
+
+var NIGHTLIGHT_GSETTINGS_SCHEMA = 'org.gnome.settings-daemon.plugins.color';
+var NIGHTLIGHT_GSETTINGS_PROPERTY = 'night-light-enabled';
diff --git a/src/modules/Nightlighter.js b/src/modules/Nightlighter.js
index 63f1c6a..d4e8138 100644
--- a/src/modules/Nightlighter.js
+++ b/src/modules/Nightlighter.js
@@ -18,6 +18,7 @@ this program. If not, see <http s ://www.gnu.org/licenses/>.
 
 const { extensionUtils } = imports.misc;
 const { Gio } = imports.gi;
+const { main } = imports.ui;
 
 const Me = extensionUtils.getCurrentExtension();
 const config = Me.imports.config;
@@ -29,39 +30,86 @@ const _ = Gettext.gettext;
 /*
 The Nightlighter establishes a connection with the session bus to get the
 current Night Light status. It can also be asked to listen to status changes.
+
+As Night Light is essential for the extension to work, it continuously checks
+if it is enabled and warns the user if that's not the case.
 */
 
 var Nightlighter = class {
 
 	constructor() {
+		this.nightlight_gsettings = new Gio.Settings({ schema: config.NIGHTLIGHT_GSETTINGS_SCHEMA });
+	}
+
+	enable() {
+		// As Night Light must be enabled for the extension to work, we have to monitor any change of that setting.
+		this._listen_to_nightlight_status();
 		try {
+			this._check_nightlight_status();
 			this._connect_to_dbus();
+			this._listen_to_nightlight_changes();
 		}
 		catch(e) {
-			throw e; // Let's pass the error up.
+			main.notifyError(config.EXT_NAME, e.message);
 		}
 	}
 
+	disable() {
+		this._stop_listening_to_nightlight_status();
+		this._stop_listening_to_nightlight_changes();
+	}
+
 	get status() {
+		if ( !this.proxy ) {
+			throw new Error();
+		}
 		try {
 			return this.proxy.get_cached_property('NightLightActive').get_boolean();
 		}
 		catch(e) {
-			return false; // If Night Light is disabled, we consider it is inactive.
+			return false; // Sometimes when Night Light hasn't changed colors yet it returns an error, we consider it is inactive.
 		}
 	}
 
-	listen(callback) {
-		this.connect = this.proxy.connect('g-properties-changed', callback);
+	subscribe(callback) {
+		this.nightlight_change_callback = callback;
 	}
 
-	stop_listening() {
-		if ( this.proxy && this.connect ) {
-			this.proxy.disconnect(this.connect);
+	emit() {
+		if ( !this.nightlight_change_callback ) return;
+		this.nightlight_change_callback();
+	}
+
+	_is_nightlight_enabled() {
+		return this.nightlight_gsettings.get_boolean(config.NIGHTLIGHT_GSETTINGS_PROPERTY);
+	}
+
+	_check_nightlight_status() {
+		if ( !this._is_nightlight_enabled() ) {
+			const message = _('Night Light must be enabled to use this extension. Please enable it in your system settings.');
+			throw new Error(message);
 		}
 	}
 
+	_listen_to_nightlight_status() {
+		if ( this.nightlight_status_connect ) return;
+		this.nightlight_status_connect = this.nightlight_gsettings.connect('changed::' + config.NIGHTLIGHT_GSETTINGS_PROPERTY, this._on_nightlight_status_change.bind(this));
+	}
+
+	_stop_listening_to_nightlight_status() {
+		if ( this.nightlight_gsettings && this.nightlight_status_connect ) {
+			this.nightlight_gsettings.disconnect(this.nightlight_status_connect);
+			this.nightlight_status_connect = null;
+		}
+	}
+
+	_on_nightlight_status_change() {
+		this.enable();
+		this.emit();
+	}
+
 	_connect_to_dbus() {
+		if ( this.proxy ) return;
 		const connection = Gio.bus_get_sync(Gio.BusType.SESSION, null);
 		if ( connection === null ) {
 			const message = _('Unable to connect to the session bus.');
@@ -82,4 +130,16 @@ var Nightlighter = class {
 		}
 	}
 
+	_listen_to_nightlight_changes() {
+		if ( this.connect ) return;
+		this.connect = this.proxy.connect('g-properties-changed', this.emit.bind(this));
+	}
+
+	_stop_listening_to_nightlight_changes() {
+		if ( this.proxy && this.connect ) {
+			this.proxy.disconnect(this.connect);
+			this.connect == null;
+		}
+	}
+
 }
diff --git a/src/modules/Switcher.js b/src/modules/Switcher.js
index adc972f..6d09fe2 100644
--- a/src/modules/Switcher.js
+++ b/src/modules/Switcher.js
@@ -54,7 +54,8 @@ var Switcher = class {
 			this.theme.listen(this._on_theme_change.bind(this));
 
 			this.nightlight = new Nightlighter();
-			this.nightlight.listen(this._apply_theme_variant.bind(this));
+			this.nightlight.enable();
+			this.nightlight.subscribe(this._apply_theme_variant.bind(this));
 
 			this._apply_theme_variant();
 		}
@@ -67,7 +68,7 @@ var Switcher = class {
 		try {
 			this.theme.current = this.variants.original;
 			this.theme.stop_listening();
-			this.nightlight.stop_listening();
+			this.nightlight.disable();
 		}
 		catch(e) {} // Since we're disabling, we'll just ignore errors.
 		finally {
@@ -78,7 +79,12 @@ var Switcher = class {
 	}
 
 	_apply_theme_variant() {
-		this.theme.current = this.nightlight.status ? this.variants.night : this.variants.day;
+		try {
+			this.theme.current = this.nightlight.status ? this.variants.night : this.variants.day;
+		}
+		catch(e) {
+			this.theme.current = this.variants.original;
+		}
 	}
 
 	_on_theme_change() {
diff --git a/src/modules/Themer.js b/src/modules/Themer.js
index afa9661..134dbb0 100644
--- a/src/modules/Themer.js
+++ b/src/modules/Themer.js
@@ -31,20 +31,20 @@ one. It can also be asked to listen to theme changes.
 var Themer = class {
 
 	constructor() {
-		this.gsettings = new Gio.Settings({ schema: config.GSETTINGS_SCHEMA });
+		this.gsettings = new Gio.Settings({ schema: config.THEME_GSETTINGS_SCHEMA });
 	}
 
 	get current() {
-		return this.gsettings.get_string(config.GSETTINGS_PROPERTY);
+		return this.gsettings.get_string(config.THEME_GSETTINGS_PROPERTY);
 	}
 
 	set current(theme) {
 		if ( theme === this.current ) return;
-		this.gsettings.set_string(config.GSETTINGS_PROPERTY, theme);
+		this.gsettings.set_string(config.THEME_GSETTINGS_PROPERTY, theme);
 	}
 
 	listen(callback) {
-		this.connect = this.gsettings.connect('changed::' + config.GSETTINGS_PROPERTY, callback);
+		this.connect = this.gsettings.connect('changed::' + config.THEME_GSETTINGS_PROPERTY, callback);
 	}
 
 	stop_listening() {
diff --git a/src/po/fr.po b/src/po/fr.po
index da41ec8..5918638 100644
--- a/src/po/fr.po
+++ b/src/po/fr.po
@@ -1,14 +1,14 @@
 # Night Theme Switcher
 # Copyright (C) 2019 Romain Vigier
 # This file is distributed under the same license as the Night Theme Switcher package.
-# Romain Vigier <>, 2019.
+# Romain Vigier <>, 2019-2020.
 #
 msgid ""
 msgstr ""
 "Project-Id-Version: Night Theme Switcher 7\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2020-02-08 23:18+0100\n"
-"PO-Revision-Date: 2019-11-25 00:28+0100\n"
+"POT-Creation-Date: 2020-02-25 20:28+0100\n"
+"PO-Revision-Date: 2020-02-25 20:31+0100\n"
 "Last-Translator: Romain Vigier <>\n"
 "Language-Team: French <none>\n"
 "Language: fr\n"
@@ -18,11 +18,19 @@ msgstr ""
 "Plural-Forms: nplurals=2; plural=(n > 1)\n"
 "X-Generator: Gtranslator 3.34.0\n"
 
-#: src/extension.js:150
+#: src/modules/Nightlighter.js:86
+msgid ""
+"Night Light must be enabled to use this extension. Please enable it in your "
+"system settings."
+msgstr ""
+"Le mode nuit doit être activé pour utiliser l’extension. Veuillez l’activer "
+"dans les réglages du système."
+
+#: src/modules/Nightlighter.js:112
 msgid "Unable to connect to the session bus."
 msgstr "Impossible de se connecter au bus de la session."
 
-#: src/extension.js:163
+#: src/modules/Nightlighter.js:125
 msgid "Unable to create proxy to the session bus."
 msgstr "Impossible de créer une passerelle vers le bus de la session."
 
diff --git a/src/po/nightthemeswitcher@romainvigier.fr.pot b/src/po/nightthemeswitcher@romainvigier.fr.pot
index b3643f9..1b37fc4 100644
--- a/src/po/nightthemeswitcher@romainvigier.fr.pot
+++ b/src/po/nightthemeswitcher@romainvigier.fr.pot
@@ -1,14 +1,14 @@
 # Night Theme Switcher
-# Copyright (C) 2019 Romain Vigier
+# Copyright (C) 2019, 2020 Romain Vigier
 # This file is distributed under the same license as the Night Theme Switcher package.
-# Romain Vigier <>, 2019.
+# Romain Vigier <>, 2019, 2020.
 #
 #, fuzzy
 msgid ""
 msgstr ""
-"Project-Id-Version: Night Theme Switcher 12\n"
+"Project-Id-Version: Night Theme Switcher 17\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2020-02-08 23:18+0100\n"
+"POT-Creation-Date: 2020-02-25 20:28+0100\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -17,10 +17,16 @@ msgstr ""
 "Content-Type: text/plain; charset=CHARSET\n"
 "Content-Transfer-Encoding: 8bit\n"
 
-#: src/extension.js:150
+#: src/modules/Nightlighter.js:86
+msgid ""
+"Night Light must be enabled to use this extension. Please enable it in your "
+"system settings."
+msgstr ""
+
+#: src/modules/Nightlighter.js:112
 msgid "Unable to connect to the session bus."
 msgstr ""
 
-#: src/extension.js:163
+#: src/modules/Nightlighter.js:125
 msgid "Unable to create proxy to the session bus."
 msgstr ""