diff --git a/chrome/content/zotero/icon.js b/chrome/content/zotero/icon.js
index a64de7e77..88caf7348 100644
--- a/chrome/content/zotero/icon.js
+++ b/chrome/content/zotero/icon.js
@@ -257,20 +257,10 @@ function getTooltipText(button) {
 			
 			// Use defaults if necessary
 			if (!text) {
-				// Get the stringbundle manually
-				Components.utils.import("resource://gre/modules/Services.jsm");
-				let appLocale;
-				if (Services.locale.getAppLocale) {
-					appLocale = Services.locale.getAppLocale();
-				}
-				// Fx <=53
-				else {
-					appLocale = Services.locale.getApplicationLocale();
-				}
 				let src = 'chrome://zotero/locale/zotero.properties';
 				let stringBundleService = Components.classes["@mozilla.org/intl/stringbundle;1"]
 					.getService(Components.interfaces.nsIStringBundleService);
-				let stringBundle = stringBundleService.createBundle(src, appLocale);
+				let stringBundle = stringBundleService.createBundle(src);
 				text = stringBundle.GetStringFromName('startupError');
 			}
 		}
diff --git a/chrome/content/zotero/xpcom/zotero.js b/chrome/content/zotero/xpcom/zotero.js
index 51c9b4600..3c4dff3fc 100644
--- a/chrome/content/zotero/xpcom/zotero.js
+++ b/chrome/content/zotero/xpcom/zotero.js
@@ -240,24 +240,13 @@ Services.scriptloader.loadSubScript("resource://zotero/polyfill.js");
 			this.locale = this.locale + '-' + this.locale.toUpperCase();
 		}
 		
-		// Load in the localization stringbundle for use by getString(name)
-		if (Services.locale.getAppLocale) {
-			var appLocale = Services.locale.getAppLocale();
-		}
-		// Fx <=53
-		else {
-			var appLocale = Services.locale.getApplicationLocale();
-		}
-		
-		_localizedStringBundle = Services.strings.createBundle(
-			"chrome://zotero/locale/zotero.properties", appLocale);
+		_localizedStringBundle = Services.strings.createBundle("chrome://zotero/locale/zotero.properties");
 		// Fix logged error in PluralForm.jsm when numForms() is called before get(), as it is in
 		// getString() when a number is based
 		PluralForm.get(1, '1;2;3;4;5;6;7;8;9;10;11;12;13;14;15;16')
 		
 		// Also load the brand as appName
-		var brandBundle = Services.strings.createBundle(
-			"chrome://branding/locale/brand.properties", appLocale);
+		var brandBundle = Services.strings.createBundle("chrome://branding/locale/brand.properties");
 		this.appName = brandBundle.GetStringFromName("brandShortName");
 		
 		// Set the locale direction to Zotero.dir
@@ -1313,19 +1302,33 @@ Services.scriptloader.loadSubScript("resource://zotero/polyfill.js");
 			return this.collation;
 		}
 		
-		if (Services.locale.getAppLocale) {
-			var locale = Services.locale.getAppLocale();
-		}
-		// Fx <=53
-		else {
-			var locale = Services.locale.getApplicationLocale();
-			locale = locale.getCategory('NSILOCALE_COLLATE');
-		}
-		
 		try {
-			// Extract a valid language tag
-			locale = locale.match(/^[a-z]{2}(\-[A-Z]{2})?/)[0];
-			var collator = new Intl.Collator(locale, {
+			// DEBUG: Is this necessary, or will Intl.Collator just default to the same locales we're
+			// passing manually?
+			
+			let locales;
+			// Fx55+
+			if (Services.locale.getAppLocalesAsBCP47) {
+				locales = Services.locale.getAppLocalesAsBCP47();
+			}
+			else {
+				let locale;
+				// Fx54
+				if (Services.locale.getAppLocale) {
+					locale = Services.locale.getAppLocale();
+				}
+				// Fx <=53
+				else {
+					locale = Services.locale.getApplicationLocale();
+					locale = locale.getCategory('NSILOCALE_COLLATE');
+				}
+				
+				// Extract a valid language tag
+				locale = locale.match(/^[a-z]{2}(\-[A-Z]{2})?/)[0];
+				locales = [locale];
+			}
+			
+			var collator = new Intl.Collator(locales, {
 				ignorePunctuation: true,
 				numeric: true,
 				sensitivity: 'base'
diff --git a/chrome/content/zotero/zoteroPane.js b/chrome/content/zotero/zoteroPane.js
index 17779a8b5..7ca1d8456 100644
--- a/chrome/content/zotero/zoteroPane.js
+++ b/chrome/content/zotero/zoteroPane.js
@@ -4697,18 +4697,10 @@ var ZoteroPane = new function()
 			var errFunc = Zotero.startupErrorHandler;
 		}
 		
-		// Get the stringbundle manually
-		if (Services.locale.getAppLocale) {
-			var appLocale = Services.locale.getAppLocale();
-		}
-		// Fx <=53
-		else {
-			var appLocale = Services.locale.getApplicationLocale();
-		}
 		var stringBundleService = Components.classes["@mozilla.org/intl/stringbundle;1"]
 			.getService(Components.interfaces.nsIStringBundleService);
 		var src = 'chrome://zotero/locale/zotero.properties';
-		var stringBundle = stringBundleService.createBundle(src, appLocale);
+		var stringBundle = stringBundleService.createBundle(src);
 		
 		var title = stringBundle.GetStringFromName('general.error');
 		if (!errMsg) {
diff --git a/chrome/skin/default/zotero/timeline/timelineControls.js b/chrome/skin/default/zotero/timeline/timelineControls.js
index 536447cf1..3ebfdcbc1 100644
--- a/chrome/skin/default/zotero/timeline/timelineControls.js
+++ b/chrome/skin/default/zotero/timeline/timelineControls.js
@@ -6,19 +6,10 @@ var lastJumpToYearValue;
  * Set up the localization string bundle from timeline.properties
  */
 function initLocaleBundle() {
-	Components.utils.import("resource://gre/modules/Services.jsm");
-	if (Services.locale.getAppLocale) {
-		var appLocale = Services.locale.getAppLocale();
-	}
-	// Fx <=53
-	else {
-		var appLocale = Services.locale.getApplicationLocale();
-	}
-	
 	var src = 'chrome://zotero/locale/timeline.properties';
 	var stringBundleService = Components.classes["@mozilla.org/intl/stringbundle;1"]
 		.getService(Components.interfaces.nsIStringBundleService);
-	return stringBundleService.createBundle(src, appLocale);
+	return stringBundleService.createBundle(src);
 }
 
 /*
diff --git a/components/zotero-service.js b/components/zotero-service.js
index 917edca11..41d1506cb 100644
--- a/components/zotero-service.js
+++ b/components/zotero-service.js
@@ -378,18 +378,10 @@ function ZoteroService() {
 							let quitStr = "Quit";
 							let checkForUpdateStr = "Check for Update";
 							try {
-								let appLocale;
-								if (Services.locale.getAppLocale) {
-									appLocale = Services.locale.getAppLocale();
-								}
-								// Fx <=53
-								else {
-									appLocale = Services.locale.getApplicationLocale();
-								}
 								let src = 'chrome://zotero/locale/zotero.properties';
 								let stringBundleService = Components.classes["@mozilla.org/intl/stringbundle;1"]
 									.getService(Components.interfaces.nsIStringBundleService);
-								let stringBundle = stringBundleService.createBundle(src, appLocale);
+								let stringBundle = stringBundleService.createBundle(src);
 								errorStr = stringBundle.GetStringFromName('general.error');
 								checkForUpdateStr = stringBundle.GetStringFromName('general.checkForUpdate');
 								quitStr = stringBundle.GetStringFromName('general.quit');