To record a fan react, click on the fan react tab below the chat.
Make sure to allow access to your camera so the video can be taken, otherwise this feature will not work.
Select your camera, and then click on the "Start Camera" button. At this time, you will see yourself in the panel and you are able to record a 5-second video of yourself. After submitting your fan react, look for it to appear at the bottom of the page so everyone can see your reaction!