I want to show another page on the dashboard page by default

Hello, as shown

I want to display another page on the dashboard page by default. When MQTT receives a message, a window pops up in the page to display other page information. When reviewing other information, click anywhere to close the pop-up window

Assumptions:
Dashboard displays A web page by default :www.google.cn

When receiving MQTT message, A small window pops up to display B page :www.youtube.com based on page A

Click anywhere to close B when I don't want to see it

Can I implement this requirement with node-red dashboard

Thank you very much