Commands with trailing slashes/symbols do not autocomplete arguments & append / when pressing tab

I am maintaining a world editor for a thirdparty server software and i am registering commands with a `/` upfront, in order to keep the commands consistent with known world editors like FAWE.

Steps to reproduce

1. Register a new command that got either a `/` or `#` or `@` as first char. As example i will use the `//set stone` command
2. Register an argument at the second slot, i.e. a string argument with the parameter name called "block"
3. Join the server
4. Be sure to have permissions for the command
5. Open the chat
6. Enter `/`
7. For bug number 1: Press <tab> as many times as wanted
8. For bug number 2: Type the command and a space, i.e. `//set `
9. For bug number 3: The registered command is `/help`; Type //help or //? and send it.

 
The observed result:

Bug number 1:

• After pressing the <tab> key, the game appends a `/` to the command. This can be repeated infinitely, ending up with a chat full of `//////`
• You can also select a command, press <tab>, and the game will put a `/` up front again, resulting in i.e. `///` as seen below!image-2021-08-14-13-53-52-507.png!

Bug number 2:

• After entering `//set `, you'd expect the game to suggest you the command parameters and enums. Instead, the command suggestion disappears entirely, and only the chat messages are shown.
  

• I have also observed the color change in the suggested commands whilst typing - which means the game knows the commands with the `/` upfront, and does not trim it in it's registry
  

 

Bug number 3:

• As `/help` is a command registered by the plugin/thirdparty server, one would expect that command to be executed.
• The client sends `Unknown command: /`.
• The server never receives a command request

 
The expected result:

• The game switches between the commands when pressing <tab> as with any other command
• The game suggests the command parameters and enums, plus lets you <tab> between the enums
• The command is known and requested on the server, so the worldedit can respond with it's custom help

 

Important note

A thirdparty server had to be used as BDS does not support adding commands / parameters without complicated modding

 

Additional information

The world editor's name is MagicWE2 if it is necessary to see how things are registered.