I was recently working on a redesign to my site that required some DOM manipulation to make HTML5 semantic content like <header> and <footer> show up. Basically, you have to create those elements on page load to get IE to render CSS effects on them.
I was running into a problem where BrowserLab showed basically a blank screen for the IE8 version of my site. It was as if the HTML5 elements weren’t being added and therefore IE 8 wouldn’t render them.
That was close to the problem, it was that the rendering didn’t happen immediately on page load. BrowserLab has a fix for this. In the upper right corner, there is a setting named “Delay”. You can use this to delay BrowserLab’s capture and therefore wait until the entire page is rendered.
An awesome little feature that makes BrowserLab that much more useful.