When a client files a dispute, customer support reviews the work diary. Any time they see a browser, they say that time is not related to the project and remove it from your billing. It doesnt matter even if the job you are hired for involves the internet or work in a browser, they auto-reject those screen shots. It would be helpful if they read the job post or project details to see if that work was part of the scope, but the agents in charge of disputes dont know much about the various types of work they actually are charged with reviewing, so they just paint any web browser time with a broad brush of "not work realated"
I know, manily because way back when I had a "scam" client who tasked me with moving their site from one place to another- which is obviously done in a web browser, and to avoid payment, they disputed the hours. oDesk ruled that the time in my diary was not work related, it doesnt matter that the project was web based, which tells me that they just see any net time as "not work related"
I hope that helps you understand.
