Install the Giphy App from the App Marketplace https://rocket.chat/marketplace.
Under Administration Settings -> Apps -> Giphy
Thanks to RocketBooster
Follow the install instructions here:
​https://github.com/FinndropStudios/GifRocket​
Thanks to Finndrop Studios
Manuel Bachl (m.bachl@finndrop.de)
Thies Schneider (t.schneider@finndrop.de)