Rated 2 out of 5 stars

I concur with previous comments that it does indeed seem to have problems running under Linux (IceWeasel in my case); I don't consider my system out of date but it is a low-end spec'.

I have waited for half a minute and upwards for a validation, before closing the menu and restarting the browser. A few times. Accordingly: still no validation; no "actual" review and the Homepage won't load (read: load, not connect). Fortunately I have found a replacement...

I do like, however, that the validation takes place directly adjacent to the source (as in M.Guery's "HTML Tidy"). I also like the number and variety of validation schemes (to validate a page against) on offer, and how they can be interfaced with.
I don't like the only way you can get to the main preferences menu (that controls the way the add-on works as well as what it validates with) is through the icon on the status bar; nor do I like that you can't remove this icon as a result.

I base this rating entirely on what I have seen so far, and provide my very munged e-mail address so the author/s can contact me if they choose. Not a complete waste of time, though not functional on my system. If interfacing with the preferences can be tweaked, the RAM demands equal that of HTML Tidy (and getting Relaxed working at all on Linux) it would be marvellous.

Rated 3 out of 5 stars

Exactly what I was looking for, but It was too slow. Even when the page was lparsed when I opened the source it started parsing again. After that i gave me some errors and not what I wanted. I'm looking forward to seeing new version, because HTML Tidy doesn't work under Linux.

Rated 3 out of 5 stars

Tidy functionality is respectable. Validation takes FOREVER. When is someone going to make an extension that is just a tidies the source?

Erratic Rated 1 out of 5 stars

Firstly it gets the validation wrong, giving different errors when you reload your page. So it's primary function is unreliable.

However, it is well integrated with firefox and gives pretty good hints on how to address errors. Pity.