Gif file, which seems to be applied visually after uploading it (that image in the screenshot is the banner I uploaded) but when applying the change, Discord says that the file cannot be larger than 10.00 MB. The current file size limit for uploading files to Discord is eight MB. Therefore, your profile picture or PFP must be within this limit. The best icon size of the Discord server is a square image of 512 × 512 pixels, which, as with the image of the avatar, is cropped in a circle.
Discord supports PNG, JPG, JPEG and even GIF formats. The upper limit of the file size for gif avatars is 50 mb, as I found out when, because I was bored, I tried to convert the entire Shelter music video by Porter Robinson into an avatar and I couldn't compress it even to twice the maximum size. If, for some reason, the gifs don't play if you upload them from the camera roll, try uploading the gifs as a file. Turn on “Automatically play gifs when possible” in the Discord settings to automatically play gifs.
In some cases, your profile doesn't sync correctly with the Discord server, so gifs don't work or upload and cause problems. When you're setting up your server, you can also add a Discord banner background image and also a Discord server invitation presentation image. To fix Discord gifs not working, you can turn off Reduce Motion from iOS settings if you're an iOS or iPadOS user. WhatsApp does not send the message as a GIF image, in fact, the message is sent as a video itself and since the video is short, it actually plays it in a loop on the screen, which looks like a GIF animation without sound.
If you use a messaging program like WhatsApp (which now supports GIFs and videos on Android), make sure that both users use the same version of the application. Sometimes, the Discord server considers the gif as an image when it is loaded from the camera roll, so uploading it as a file solves the problem. In that case, instead of uploading gifs from the gallery or internal storage, use a gif app like GIFY to upload or share gifs. If you're trying to upload a gif as an avatar, make sure you have at least one Discord Classic subscription.
There's also a premium paid version of Discord called Discord Nitro, which offers all sorts of cool boosters like custom emojis, animated avatars, and more. Another thing to keep in mind is that Discord can't crop gif avatars to a square like it does (if I remember correctly) for normal images. Turning on the option “automatically play gifs when possible” fixed the issue for desktop and Android users. But for many users, a poor internet connection causes the gif to not load properly, and the Discord server gets a damaged gif file that it can't play.