I have two operating systems: Windows 8.1 and Ubuntu 14.04. I want to hide grub menu. I'm using grub 2.02~beta2-9. I tried following combinations of /etc/default/grub:

1. #GRUB_HIDDEN_TIMEOUT=1  
   
   #GRUB_HIDDEN_TIMEOUT_QUIET=true  
   
   GRUB_TIMEOUT=0
   
   

   
   
   

   grub menu is visible for 10 seconds (if timeout is set for value larger than 0 it is displayed correctly: GRUB_TIMEOUT=5 - 5 seconds delay)




2. GRUB_HIDDEN_TIMEOUT=1  
   
   GRUB_HIDDEN_TIMEOUT_QUIET=true  
   
   GRUB_TIMEOUT=0 
   
   

   
   
   

   grub menu is visible, I also tried GRUB_HIDDEN_TIMEOUT=false and setting both GRUB_TIMEOUT and GRUB_HIDDEN_TIMEOUT to zero and non-zero values




3. #GRUB_HIDDEN_TIMEOUT=1  
   
   #GRUB_HIDDEN_TIMEOUT_QUIET=true  
   
   GRUB_TIMEOUT=1  
   
   GRUB_TIMEOUT_STYLE=hidden
   
   

   
   
   

   grub menu is visible for 1 second, tried also GRUB_TIMEOUT_STYLE=countdown with the same result, if GRUB_TIMEOUT is set to 0, 10 seconds delay

After each change I type update-grub and restart computer to see the results.

According to GRUB documentation found in info -f grub -n 'Simple configuration' second way is deprecated. The right way is the third one - by using GRUB_TIMEOUT_STYLE, but unfortunately it doesn't work. It's probably some kind of a bug.