Multi-window icon is disabled after upgrading samsung galaxy tab from 4.1.2 to 4.2.2.
Anybody fixed this problem ? Any idea how to fix this without doing a factory reset ?
A factory reset seems to work for some people. You might want to back-up your files / data before doing this.
You can get back all the options by going to Settings > My device > Home screen mode > Standard mode. Now, all your missing options are there.
For multitasking, enable multitasking from notification tray then long press the 'back button' to have sidebar appears on screen. Now, you can enjoy multitasking back.
Just hold the back key and it will come back. It's probably in hidden mode since the icon is highlighted and showed as ON in the screenshot provided.