The Discord Crash Gif - https://gfycat.com/boilingmarriedcalf
Over the course of Discord history there have been various methods to crash discord, some that have been patched out include special unicode characters, a special image I couldn't get a hold of myself, and a special gif that used to crash IOS users.
NOT patched out are videos that abuse -going in with a RGBY color editor and changing to an invalid color -editing sound above the sound barrier -using (I believe) FFMPEG to stitch together videos of different resolutions together.
Now about the last one; chromium does not account for the possibility of a video changing resolution mid-way through, so the video player "throws up an error, shits itself, and takes down discord with it--in some cases even your operating system too" - paraphrased.