Changing the welcome message of the chatbox does not affect how the Crisp chatbox works.
Here's how to proceed:
Login to: https://app.crisp.chat/
Go to your website settings: click on the "Settings" icon on the left sidebar, then click on "Websites" and select the target website in the list
Select Chatbox & Email settings
Go to chatbox appearance
Select your message in "Welcome Message"
Your message is auto-saved
Published on: 03 / 11 / 2017