I think he means that firefox has the tabs available to click on, but not actually loaded until you click on them. Chrome goes and opens every page when it come

I think he means that firefox has the tabs available to click on, but not actually loaded until you click on them. Chrome goes and opens every page when it comes back up, and ends up with a substantial (re)startup time due to it, especially by the time you're around 100 or so tabs in Basically, firefox does lazy loading, and chrome does not