It seems like beta 9 is causing a problem with the taskbar. I have it set up to "Enable multiple taskbars" and "All taskbars show relevant windows." When beta 9 installed, I started having the problem of when I moved a window from one monitor to another, the full taskbar button (showing the program was open) would appear on both monitors. This was especially the case after coming out of hibernation for some reason.

In any event, a reversion back to beta 8 has made the problem go away. I'm reporting so it can get fixed. Thanks!

all applications. the problem went away when trintalling beta 8