Thank you so much for dealing with my problem! Honorable!
It works for me, in all browsers.
That error message doesn’t appear in Chrome (the page simply appears without a slider). There is also an error message in the “Edge” browser.
+ One more question: The description of the template says that the ‘revolution slider’ plugin is included in the full version, but in my case the software asks me to activate it.
Did I mess something up?