OpenDialog Docs
OpenDialog 2023.1

Message type: Text block

Text message type
A text message is a plain message with only text. You can add as many text blocks to your message as required. If you want to include a link, you can do this by pasting in the full URL, this will then be shown as a clickable link once displayed in OpenDialog's Webchat.
Message editor: Text messages
There is no support at the moment for any other formatting such as hyperlinking text, bold, italics etc.
Saves Message: Always remember to hit 'Save Message' before closing or navigating away from the edit screen.