I've noticed that within the last week or so, the banner adverts that load up on the right hand side whilst on Census pages are being rotated/refreshed.
This has the knock on of causing issues with browser back buttons, which by going back one step, now loads in the previous banner, and not the main page itself.
I'm now finding where I am recording details of a large family, by the time I use the back button, dozens of "click me" pages have been added to my browser history.