diff --git a/core/modules/update/src/Form/UpdateManagerInstall.php b/core/modules/update/src/Form/UpdateManagerInstall.php
index 6f60fb1..ef2898b 100644
--- a/core/modules/update/src/Form/UpdateManagerInstall.php
+++ b/core/modules/update/src/Form/UpdateManagerInstall.php
@@ -104,7 +104,9 @@ public function buildForm(array $form, FormStateInterface $form_state) {
     $form['project_upload'] = array(
       '#type' => 'file',
       '#title' => $this->t('Upload'),
-      '#description' => $this->t("If you download a zip or tar.gz to your computer click 'choose file' to upload it."),
+      '#description' => $this->t("If you downloaded a file such as name.tar.gz to your computer, upload it here. Supported file types: %extensions.", array(
+        '%extensions' => archiver_get_extensions(),
+      )),
     );
 
     $form['actions'] = array('#type' => 'actions');
diff --git a/core/modules/update/update.routing.yml b/core/modules/update/update.routing.yml
index 121ca5a..f422cc5 100644
--- a/core/modules/update/update.routing.yml
+++ b/core/modules/update/update.routing.yml
@@ -63,7 +63,7 @@ update.theme_install:
   path: '/admin/theme/install'
   defaults:
     _form: '\Drupal\update\Form\UpdateManagerInstall'
-    _title: 'Install new theme'
+    _title: 'Get new themes'
   requirements:
     _permission: 'administer software updates'
     _access_update_manager: 'TRUE'