Hi, I'm a texture developer, actually in process on creating some animated texture I found some bug with flipbook_textures.json:

in 1.10.4 beta if I accelerate the animation of command block's texture from 10 to 2 tick per frame, they still on default 10, won't accelerate, in all previous version that work well.

In 1.10.4 beta the animation of smithing_table_side work well, in 1.9 is freezed on the first frame (I know that textures are different names between versions, is not this a problem)

fletcher_table_side animation won't work in any case or version, freezed on first frame

For the moment I found just that, but I'm sure if I test more I can found more.

In time I created a lot of custom animated textures, and im sure it's not my fault.