The moment you insert a link (from your browser's address bar), you will notice that LessonUp inserts it as text. This text is then not clickable as a link. Therefore, you need to specify in LessonUp that you want to include the text as a link.

If you want to create a link in a slide, you must first select a word or sentence in the slide. Then you can use the button that looks like a chain to add a link.

Add the link and press 'Ok'

The word or phrase is now underlined, indicating that a link has been made to an external website.

Good to know: the website will always open in a new tab during the lesson.