Whenever you want to add a link in some Elementor widget you may notice that you are forced to enter a full URL even if the URL you want to point to is an existing page or post in your website. So each time you add a domestic URL you need to go to that page/post and copy the link then go back to the page you edit and paste the link. When you finish building a website you will need to go to Elementor Tool >> Replace URL to change all link to the new domain.
Actually we never understood why Elementor done it that way but after building many sites we found it pretty unusable. So in our latest version: 2.2.6 we decided to change this in all Premium Addons Elementor widgets to make it easy for our users. Now You can simply choose the page/post you want to link to by starting typing it’s name and you will find the relevant items appear in a dropdown list to choose from.