This is a Tampermonkey script (browser extension) which adds a Message Translations tab to your teams GitHub page.
The script parses /conf/messages files in your teams repositories and presents a dashboard highlighting where welsh translations are missing.
Install Tampermonkey Chrome/Firefox browser extension.
Right click here and select open in new tab, you should see a prompt to install the script into Tampermonkey.
Visit your teams github page (i.e. https://github.com/orgs/hmrc/teams/), you should see a new tab 'Message Translations', click on that to open the dashboard.