Well, you cant delete messages from the Chat without messing it up but there is a function you can use. RegisterProcessCommandsFunction https://developer.roblox.com/en-us/articles/Lua-Chat-System/API/ChatService
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How to delete single/multiple/all Facebook messages
At this time, System Messages from Roblox can be deleted, but regular messages from other players cannot. If you would like to clear messages out to have a clean inbox, we do have the Archive action.
The Archive action will move messages from your inbox to your Archive tab. To archive a message, while viewing it, simply click the Archive button located below the navigation tabs.
If you’re using a PC, follow the steps below to disable the in-game chat:
Many enjoy playing Roblox games on a smaller screen. If you’re one of them and want to disable chat using the mobile app, follow these instructions:
Roblox Studio is the platform for building Roblox games, available for both Windows and Mac.
Since Roblox is child-friendly and offers a wide range of games for the younger audience, it does everything to keep them protected. It enables parents to track their children’s activity, filters out profanity, inappropriate language, personal information, etc. One of the available options is Safe Chat.
As mentioned, Roblox offers numerous child-friendly games and ensures children’s online safety while playing. If your child enjoys playing games online, you can create an account under your name and keep track of their Roblox activity.
As a child-friendly service, Roblox is focused on protecting its users’ privacy and safety. Chatting with other users is often helpful and fun, but Roblox limits the chat options depending on the users’ age. That way, Roblox ensures there’s no inappropriate language or personal information sharing.