Highlight text in Firefox

Sometimes when reading a long text in Firefox there'll be a sentence or two you want to come back to and think about again, or paste somewhere else, in blog like this for example. But if you're like me, you've probably scrolled back up the page and spent several minutes looking for the passage again, trying to remember the words and spot them in the expanse of text.
A highlighter is the answer of course. There used to be a Firefox extension that did this, but it stopped being updated a long time ago and isn't usable with recent versions of Firefox. There are more sophisticated extensions available that include a permanent highlight function (like Wired-Marker), but I'm not doing research so their functions are largely superfluous.
I was having a look at extensions again yesterday and was happy to find a basic Firefox text highlighter that works with recent versions of Firefox. It's called TextMarker!

Update: Blogger users may not appreciate the way this extension adds a load of HTML every time you paste something into the comment field.