diff --git a/public/src/app.js b/public/src/app.js
index a20aaf0bde..68cfd9024f 100644
--- a/public/src/app.js
+++ b/public/src/app.js
@@ -353,7 +353,7 @@ app.flags = {};
 
 	function registerServiceWorker() {
 		// Do not register for Safari browsers
-		if (!ajaxify.data._locals.useragent.isSafari && 'serviceWorker' in navigator) {
+		if (!config.useragent.isSafari && 'serviceWorker' in navigator) {
 			navigator.serviceWorker.register(config.relative_path + '/service-worker.js', { scope: config.relative_path + '/' })
 				.then(function () {
 					console.info('ServiceWorker registration succeeded.');
diff --git a/src/controllers/api.js b/src/controllers/api.js
index 984ea98e42..1194a75399 100644
--- a/src/controllers/api.js
+++ b/src/controllers/api.js
@@ -81,6 +81,7 @@ apiController.loadConfig = async function (req) {
 		},
 		iconBackgrounds: await user.getIconBackgrounds(req.uid),
 		emailPrompt: meta.config.emailPrompt,
+		useragent: req.useragent,
 	};
 
 	let settings = config;
diff --git a/src/middleware/render.js b/src/middleware/render.js
index 6957f5a6d2..8555ee9314 100644
--- a/src/middleware/render.js
+++ b/src/middleware/render.js
@@ -65,7 +65,7 @@ module.exports = function (middleware) {
 					req.app.set('json spaces', global.env === 'development' || req.query.pretty ? 4 : 0);
 					return res.json(options);
 				}
-
+				const optionsString = JSON.stringify(options).replace(/<\//g, '<\\/');
 				const results = await utils.promiseParallel({
 					header: renderHeaderFooter('renderHeader', req, res, options),
 					content: renderContent(render, templateToRender, req, res, options),
@@ -76,7 +76,7 @@ module.exports = function (middleware) {
 					(res.locals.postHeader || '') +
 					results.content
 				}<script id="ajaxify-data" type="application/json">${
-					JSON.stringify(options).replace(/<\//g, '<\\/')
+					optionsString
 				}</script>${
 					res.locals.preFooter || ''
 				}${results.footer}`;