Rocket.chat: Do not allow the username "all"

[BackIsBachus]

Your Rocket.Chat version: 0.31.0

Hello there,

I don't think I saw this mentioned elsewhere (but correct me if it is), but you can create a user whose username is... all

I know it is silly but is highly problematic because you can't just mention this user in a conversation it will highlight everyone in the channel (the normal @all behaviour). Although the auto-completion shows 2 options the outcome is the same.

(Sorry for the French interface :fr: )

So I think it should not be possible to choose this specific username because someone someday will have the same idea again (also I don't think trusting the end-user on this one is a wise move ^^).

[Syirrus]

I think the @all is problematic in that it can be spammed. Maybe in addition to preventing someone from using this "reserved name" we can also limit the @all usage to only moderators or admins

[mnt]

@RocketChat/core

Well we could add all as a default blocked username:
https://github.com/RocketChat/Rocket.Chat/pull/3589

What do you guys think?

[louisemessage]

Tested in 2.10.5 and this is still an issue

[ggazzo]

fixed :)