LVHA

I've always provided a "visited" state using CSS. I do it in primary content only. I typically will not touch primary navigational elements. Those will keep the same LV and use different HA to accentuate the link when the cursor is passed over it or an action is made by the user.

3.9 Generated content techniques
[w3.org...]

If you really want to get serious about providing indication on whether a link has been visited or not, you might do something like this...

The phrase "Visited link:" is inserted before every visited link:

A:link  { color: red } /* Unvisited links */
A:visited { color: green } /* Visited links */
A:visited:before { content: "Visited link: " }

There are some pretty nifty CSS strategies that can be employed in the "visited" visual. ;)

Just the same, it's the way it's supposed to be done, so I do it.

On my own sites I leave them to default to the settings in the users' browsers. That way I don't confuse anybody who likes them like that, and anybody who really hates the default will probably take the trouble to learn how to change the settings.

Many, many sites suppress the visited link state these days, but from an accessibility point of view that's not necessarily the best thing to do.