add missing i18n for sidebar

views/snippets/footer.html

@@ -428,6 +428,10 @@
     sidebar_see_less: "{{ t('sidebar.see_less') }}",
     sidebar_show_full_comment: "{{ t('sidebar.show_full_comment') }}",
     sidebar_loading_activity: "{{ t('sidebar.loading_activity') }}",
+    sidebar_no_activity: "{{ t('sidebar.no_activity') }}",
+    sidebar_failed_to_load: "{{ t('sidebar.failed_to_load') }}",
+    sidebar_loading_more: "{{ t('sidebar.loading_more') }}",
+    sidebar_end_of_activity: "{{ t('sidebar.end_of_activity') }}",
     select_file: "{{ t('upload_btn.select_file') }}",
     enter_url: "{{ t('upload_btn.enter_url') }}",
     tags_required: "{{ t('upload_btn.tags_required') }}",