Shortly updating to Ubuntu Trusty (14.04), I noticed the following warning on my console during updates. I finally got around to looking into it deeper and found that many users have seen this too.
Warning: Setting GRUB_TIMEOUT to a non-zero value when GRUB_HIDDEN_TIMEOUT is set is no longer supported.
If you edit the ‘grub’ file, you can comment out the GRUB_HIDDEN_TIMEOUT line by adding a hash in front of it.
sudo vi /etc/default/grub
Verify that the error is fixed by executing the following:
sudo update-grub
If you are interested, you can also go and look at the updated ‘grub’ file at
/boot/grub/grub.cfg
NOTE: I’d also seen that the following command could be used, but it was of no use in my testing.
/usr/share/grub/default/grub
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