It's very annoying to accidentally refresh the page or accidentally close the tab and disconnect from the webclient, losing your log in the process. I've personally done this upwards of 10-15 times in the past year.
You know when you're on a website and you go to close it and you get a popup telling you if you do your changes might not be saved? That's called an onbeforeunload event, and I think it'd be really nice to have it as an option to enable in the webclient, so if you try to refresh or close the tab it makes you confirm it.