Updated Managing Wagtail translations (markdown)

Managing-Wagtail-translations.md

@@ -40,6 +40,8 @@ To be done periodically, particularly after any piece of development that involv
     cd wagtail/wagtailfoo
     django-admin makemessages --locale=en --extension=html,txt,py,js
 
+NOTE: `django-admin` is run from the app's root, NOT the 'locale' folder.
+
 (Specifying js in `--extension` ensures that translations in our JS templates, e.g. /wagtail/wagtailimages/templates/wagtailimages/chooser/chooser.js, are picked up. If in future we eliminate these JS templates, it should be fine to leave the `--extension` switch out here.)
 
 Then, from the root of the Wagtail codebase: