Go to Web Chat.
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Click Chat Windows,You can choose a color for the window, set the chat window's Header, choose the chat window's Style (Classic, Circle, or Bubble), Change the chat window Background, and edit Window Title according to your needs.
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Click the Options for Visitors section to adjust which operation(s) will be available on the chat window.
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Click the Advanced section to adjust operation(s) to end the chat automatically when the visitor doesn't respond, send the chat transcript over email, limit the chat queue length. Enter Greeting Message which will display at the top of Chat Window.
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Click Save.
Click Live Preview button, you can view Preview.