Copilot chat experiences in Microsoft 365 and Windows use the Enter key to send the message. To insert a new line instead of sending, use the standard multi-line shortcut:
- Press Shift + Enter to go to the next line while composing your message.
- Press Enter alone when ready to send.
Microsoft’s Copilot help articles in the provided context describe using the Enter key to send prompts (for example, in Microsoft 365 Copilot Chat, Outlook with Copilot, and the Microsoft 365 Copilot app), but do not document an alternative key specifically for line breaks. The Shift + Enter shortcut is the typical behavior for multi-line text fields in Microsoft apps.
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