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Whenever I boot my computer, I do not get any boot-menu to choose OS. It neither boots until I keep pressing ENTER (return). When it finally boots, it boots into UBUNTU and not windows. When earlier I used to get boot-menu, UBUNTU was the first option so presumably on pressing ENTER it is booting in UBUNTU.
Here is output from boot-repair. http://paste.ubuntu.com/p/kNw2DfHKMk/
The boot repair doesn't recognize Windows 10 installation in sda4: http://paste.ubuntu.com/p/FWSJ4zH7NT/