diff --git a/app/assets/javascripts/discourse/adapters/group.js.es6 b/app/assets/javascripts/discourse/adapters/group.js.es6
new file mode 100644
index 00000000000..34134b50ea3
--- /dev/null
+++ b/app/assets/javascripts/discourse/adapters/group.js.es6
@@ -0,0 +1,7 @@
+import RestAdapter from 'discourse/adapters/rest';
+
+export default RestAdapter.extend({
+  appendQueryParams(path, findArgs) {
+    return this._super(path, findArgs, '.json');
+  },
+});
diff --git a/app/assets/javascripts/discourse/adapters/rest.js.es6 b/app/assets/javascripts/discourse/adapters/rest.js.es6
index c826bbefc9c..e33a755970b 100644
--- a/app/assets/javascripts/discourse/adapters/rest.js.es6
+++ b/app/assets/javascripts/discourse/adapters/rest.js.es6
@@ -40,7 +40,7 @@ export default Ember.Object.extend({
     return "/";
   },
 
-  appendQueryParams(path, findArgs) {
+  appendQueryParams(path, findArgs, extension) {
     if (findArgs) {
       if (typeof findArgs === "object") {
         const queryString = Object.keys(findArgs)
@@ -48,11 +48,11 @@ export default Ember.Object.extend({
                                   .map(k => k + "=" + encodeURIComponent(findArgs[k]));
 
         if (queryString.length) {
-          return path + "?" + queryString.join('&');
+          return `${path}${extension ? extension : ''}?${queryString.join('&')}`;
         }
       } else {
         // It's serializable as a string if not an object
-        return path + "/" + findArgs;
+        return `${path}/${findArgs}${extension ? extension : ''}`;
       }
     }
     return path;
diff --git a/config/routes.rb b/config/routes.rb
index 69b7b2fbef7..8a96931a8ed 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -626,7 +626,7 @@ Discourse::Application.routes.draw do
     get "private-messages-archive/:username" => "list#private_messages_archive", as: "topics_private_messages_archive"
     get "private-messages-unread/:username" => "list#private_messages_unread", as: "topics_private_messages_unread"
     get "private-messages-tags/:username/:tag_id.json" => "list#private_messages_tag", as: "topics_private_messages_tag", constraints: StaffConstraint.new
-    get "groups/:group_name.json" => "list#group_topics", as: "group_topics"
+    get "groups/:group_name" => "list#group_topics", as: "group_topics", group_name: RouteFormat.username
 
     scope "/private-messages-group/:username", group_name: RouteFormat.username do
       get ":group_name.json" => "list#private_messages_group", as: "topics_private_messages_group"
diff --git a/test/javascripts/acceptance/group-manage-logs-test.js.es6 b/test/javascripts/acceptance/group-manage-logs-test.js.es6
index 26446972942..95c76dc70a6 100644
--- a/test/javascripts/acceptance/group-manage-logs-test.js.es6
+++ b/test/javascripts/acceptance/group-manage-logs-test.js.es6
@@ -11,7 +11,7 @@ acceptance("Group logs", {
       ];
     };
 
-    server.get('/groups/snorlax', () => { // eslint-disable-line no-undef
+    server.get('/groups/snorlax.json', () => { // eslint-disable-line no-undef
       return response({"group":{"id":41,"automatic":false,"name":"snorlax","user_count":1,"alias_level":0,"visible":true,"automatic_membership_email_domains":"","automatic_membership_retroactive":false,"primary_group":true,"title":"Team Snorlax","grant_trust_level":null,"incoming_email":null,"has_messages":false,"flair_url":"","flair_bg_color":"","flair_color":"","bio_raw":"","bio_cooked":null,"public":true,"is_group_user":true,"is_group_owner":true}});
     });
 
diff --git a/test/javascripts/fixtures/group-fixtures.js.es6 b/test/javascripts/fixtures/group-fixtures.js.es6
index c0dd3a567b7..4493e65df7b 100644
--- a/test/javascripts/fixtures/group-fixtures.js.es6
+++ b/test/javascripts/fixtures/group-fixtures.js.es6
@@ -1,5 +1,5 @@
 export default {
-  "/groups/moderators":{
+  "/groups/moderators.json":{
     "group": {
       "id": 50,
       "automatic": true,
@@ -32,7 +32,7 @@ export default {
       "messageable": true
     },
   },
-  "/groups/discourse":{
+  "/groups/discourse.json":{
     "group":{
       "id":47,
       "automatic":false,