In iOS on my instance sh.itjust.works in the Voyager app, I can hold my finger down on a gif, then I can either copy it and paste it into my comment, or I can add it to the photos app which then makes it available down the road anytime I want because they are all organized into the ‘animated’ category in photos. On MacOS in safari I actually have to right click the gif and save the file to the folder. At this point wherever I am if I am in voyager I then click the ‘picture’ button in the voyager comment toolbar and either browse for my animated photo or browse my folders for the GIF file.