Automatically check for valid HTML on each request

I am cleaning up my website and i would like to see html errors and warnings on each page automatically. I use to use Html Validator for firefox (addon) but it doesnt appear to validate automatically anymore. I don't know if its because of the addon version or the fact i use firefox 4.

I ne开发者_如何学Pythoned to check every page request until i get through the entire site w/o errors. What addon/tool might i use?

Try this tool

Specify your web-site address and enable "Validate entire site" checkbox.