Thank you for the update, Tomas!
The message is now gone, but another message seems to like to persist:
“Thank you for using Tiny Framework! Please check out a valuable user guide: How to use Tiny Framework and its child themes: a comprehensive guide. Happy coding!”
This one actually has the (X) button on the right edge, and clicking on it dismisses the message. However, what I am seeing on my setup is that message comes back after I click on any other WP option (like “Pages”, “Users”). Could it simply be the new code missed that one message?