Some windows, I've noticed, don't like to snap at the bottom of them, such as Discord. I've also seen this with Chrome tabs I've launched as apps (creating a shortcut with the target as "C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --app=https://www.displayfusion.com/)

I've attached two screenshots showing this behavior. I'm thinking, since Discord I believe uses Chrome as its engine, it's something that happens only chrome "apps".