Set the system language as the default for user profiles

src/routes/profile.js

@@ -29,7 +29,8 @@ const assert = require('assert'),
     safe = require('safetydance'),
     tokens = require('../tokens.js'),
     userDirectory = require('../user-directory.js'),
-    users = require('../users.js');
+    users = require('../users.js'),
+    settings = require('../settings.js');
 
 async function canEditProfile(req, res, next) {
     assert.strictEqual(typeof req.user, 'object');
@@ -58,7 +59,7 @@ async function get(req, res, next) {
         role: req.user.role,
         source: req.user.source,
         hasBackgroundImage: !!backgroundImage,
-        language: req.user.language,
+        language: req.user.language || await settings.get(settings.LANGUAGE_KEY),
         notificationConfig: req.user.notificationConfig,
     }));
 }