A long-standing privacy issue has existed with users being allowed to include arbitrary images from arbitrary external domains in posts and chat. This can be used to track users, among other risks.
Additionally, off-site images can rot or have their contents changed. And while this is a more minor issue, my school district (and like others using the same software) cuts off internet access if banned applications/websites are detected, and off-site hosted images from Discord's CDN or NSFW websites can cause this to happen without ever leaving Stack Exchange.
If you'll already be needing to rehost a significant majority of images on the site, are there any plans to finally disallow off-site image hosting on untrusted sites?