I've been having this problem since the early builds, but it seems to get worse the longer I have 10 on my machine. While browsing the internet (and other times not doing anything but watching a movie) the "choose a default app" dialog will appear, asking me to choose between Windows Script Host or Java, or some other 3rd app that isn't relevant. Even after making sure "always use this app to open .js files" is checked, the dialog will appear later on in the day. Going through the file type settings does nothing either, and will still bring up the dialog later. It does not matter if/when I have restarted Windows either.

Please help!