To add images and icons to your agenda, you need to copy the image URL and paste it into the agenda editor. For more information on how to add an image to your agenda, check out this article.
Make sure that you copy the URL with no spaces on either side, otherwise the image will not be copied correctly.
At Circles we’ve created a list of some of our most popular icons and images used in agendas, including the +1 and handraise icons. Each image has its own URL and the smaller icons also have suggested sizings, all of which are below.