At first I used the window.blur/focus events but noticed it would also stop refreshing if tab is active but browser window is not active. I reckon many people might want to leave the browser open in one window and follow the live visitors while working on something else. That's why we should use the page visibility API which is supported by most browsers (I think not in <= IE9). I used a different library first but noticed it adds many event listeners like mousemove etc and it can make Piwik slow so used the visibility.js library in the end. If someone uses an old browser nothing will change compared to before so that should be ok. In a next version we could initiate a refresh immediately once the browser tab becomes active again.
Hey, that's a nice change!
That's why we should use the page visibility API which is supported by most browsers
:+1: Moved to 2.10.0
:+1: thank you! Good point about the "inactive but visible" situation, too.