https://pastebin.com/jiwyceUM
https://cdn.discordapp.com/attachments/989441510552514562/995526979271012433/unknown.png

Can confirm. Restart dos not help.
Messes up:

Chat messages
Command Responses
System Messages
Player Joins
and more

The mod Jar contains the file assets/minecraft/lang/en_us.json with the contents:

{
  "block.minecraft.sand": "Sand Block",
  "block.minecraft.red_sand": "Red Sand Block"
}

This is effectively wiping all the aliases for the logger and setting just 2.

Editing the Jar and removing this file will make the server use the default language file.

Happens to me as well

The mod Jar contains the file assets/minecraft/lang/en_us.json with the contents:

{
  "block.minecraft.sand": "Sand Block",
  "block.minecraft.red_sand": "Red Sand Block"
}

This is effectively wiping all the aliases for the logger and setting just 2.

Editing the Jar and removing this file will make the server use the default language file.

Makes sense
thanks now the devs just have to fix it

fixed for upcoming version