- "Copy link" on images is now producing an image link that has "ex", "is" and "hm" URL parameters
- The parameters can be removed (or altered) without affecting the link's validity (at least, for now)
- "ex" means expiry, "is" means issue time. Both are expressed as hexadecimal numbers encoding a UNIX timestamp. "is" is the time when the link is generated. "ex" is exactly 86400 seconds (24 hours) after the issue time.
- "hm" likely means HMAC. It looks like a SHA-256 hash, and is likely an HMAC-SHA-256 of the link, ex and is parameters. It's not currently being validated, but it would not surprise me if Discord is internally tracking failures on hashes and expiry parameters.