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After upgrading to Ubuntu 19.04 my GRUB menu doesn't not show up.
Instead, it halts for 10 seconds and then directly boots up to 19.04 although I have installed Windows 10 alongside (Dual booted).
GRUB menu was working perfectly when upgrading to 18.10 from 18.04LTS.
Also, if I press Esc or Shift key it hangs and then I have to press power button to start the laptop again.