The block break animation for other players damaging blocks does not animate on Forge servers (tested on forge-1.8.9-11.15.0.1715, works on vanilla 1.8.9 and Spigot), instead it stays on the very first stage:
compare to vanilla 1.8.9, you see all of the stages of the animation:
In both cases, using the same 1.8.9+forge-1.8.9-11.15.0.1715 client (probably not relevant, but also have installed mods/ironchest-1.8.9-6.0.121.768.jar)
The block break animation for other players damaging blocks does not animate on Forge servers (tested on forge-1.8.9-11.15.0.1715, works on vanilla 1.8.9 and Spigot), instead it stays on the very first stage:
compare to vanilla 1.8.9, you see all of the stages of the animation:
In both cases, using the same 1.8.9+forge-1.8.9-11.15.0.1715 client (probably not relevant, but also have installed mods/ironchest-1.8.9-6.0.121.768.jar)