Link to the video explaining Transifex

Author: dhruvkb

content/contributing-code/translation-guide/contents.lr

@@ -16,6 +16,9 @@ diverse user base.
 We use Transifex to manage our translation files. It provides an intuitive UI
 and many useful tools. Let's see how you can join us there and get started.
 
+TL;DR: We have a [video version](https://www.youtube.com/watch?v=Rta2AlPww8M)
+of this tutorial if you prefer that as the medium of instruction.
+
 ## For translators
 
 * **Sign up on Transifex**