[firefax]

there's also an apng standard that almost noone makes use of despite not being patent uncumbered like gif is and it does a good job compressing more "pixel art" or line drawings in the way gif does. (tends to be a bit less efficient with actual photographs)

[duskwuff]

It's actually supported in all major browsers now, too: https://caniuse.com/apng

And even in software which don't support APNG, it'll render as the first frame of the animation, which is probably a fine fallback.

[mkl]

GIF hasn't been patent-encumbered since 2004. APNG was initially released in 2004. MNG was earlier, but didn't catch on.