I have the solution
1. Use element Heading instead of Text Editor.
2. Set the property “HTML tag” = “p” instead of “H1” in the settings section for the Heading.
2. Element Heading has the “link” attribute that can link to ACF URL
Done!
This is not so user-friendly, but it is.
The main problem is that ACF-type “URL” works only with the “Link” attribute of elements in Elementary. You can check any Elementor’s element that has a “Link” attribute, for example with a Button or Video – and this works fine.