If you want to highlight texts on the internet, don't underline them! Form them in Boldface or Italics or different colour but do not underline them.
Underlined texts are automatically THE identification sign that it is a hyperlink, i.e. the redirection to another page.
If a user clicks on an underlined text and nothing happens at first, he or she is confused or frustrated.
That is a basic rule, but since when has that actually been the case? Blue underlined links are now so burned into the brain that they are only perceived subconsciously as a self-evident design element.
But when did hyperlinks actually start to exist? I got to know the first ones at university in 1994 and they were already underlined and had a blue colour. Links that you had visited had a purple colour. And before that? A search then revealed that other people had already thought about this, in other words: there are an astonishing number of people who no longer do anything sensible in life.
At the forefront are the people from Mozilla itself, the makers of Firefox. Researching the first blue links is at the same time a nostalgic look back at a time when the internet was still new territory (at least that's how I felt at the time). Here is the article:
The first blue link appeared in the Mosaic browser on 12 April 1993. Keep that to yourself, though, if you want to pass as a socially integrated person.