If you’re using the new chat, then setting chat bubbles to specific colors for specific players is not a feature yet, you can only change it for all players at once.
If you’re using the old chat, I have a somewhat digestible tutorial:
Run your game in Studio and use the Explorer to grab the default Chat scripts:
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You’re going to want the Client chat scripts specifically, as they are the ones related to creating chat bubbles.
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Chat bubbles are created in the BubbleChat script, for example when this:OnPlayerChatMessage is ran.
I haven’t made a system to change the chat color based on what channel they use, but I’m pretty sure in the OnNewMessage.OnClientEvent function, messageData is a table that contains the chat channel they use. You can’t really find a Roblox Developer link to what messageData contains, so you can just print the table yourself and try and go through and pick out what you need, example:
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Here’s come code that we use in the CreateChatLineRender function for our game, where we change a chat bubble to black with golden-ish text:
bubbleText.TextColor3 = Color3.fromRGB(255, 255, 185)
bubbleText.TextStrokeColor3 = Color3.fromRGB(0,0,0)
bubbleText.TextStrokeTransparency = 1
chatBubbleRender.ImageColor3 = Color3.fromRGB(0,0,0)
chatBubbleRender.ChatBubbleTail.ImageColor3 = Color3.fromRGB(0,0,0)
I hope this helps a little. The old chat system is a bit archaic and hard to work with for stuff like this.