Click the floating plus icon in the lower right of a folder
Select "Tooltip Guide"
Enter a name for this tooltip
Add a URL rule where you want to place the tooltip
Select "Power HTML"
To make it work, we have to select an HTML field
Enter the message you want to be displayed in the empty field
Click on "Save"
Publish this tooltip and it's respective parent folders
You will see that the empty HTML field will now display the message you provided
Here is the tooltip in action