As you know, you can add a link to To a Heading or a Button widget in the Elementor.
Beware! Heading and Button element is a part of the Raven elements. Raven is an exclusive plugin developed by Artbees which represents new useful elements to Elementor. In order to see the default Elementor Heading and Button, you need to look for it in the Elementor knowledgebase.
To open added URL in a new window follow the steps below:
1. Search for Heading or Button widget in Elementor dashboard.
Note: To learn how to add a Heading widget in Elementor, you can refer to this article.
2. A new dashboard on the left will open with the element’s settings.
3. In the Content tab and from Link section, add your link and click on Gear icon to open Link options.
4. Make sure Open in new window is checked.
5. Update the Page.