While these are cool, I honestly wish GRUB was silent unless you’re holding a key during boot. The 5 seconds it takes to go away and just boot the OS by default is really unnecessary.
Why would you actually want this? Such a weird desire to hide this kind of stuff because it's so inconsequential in my mind.
I'm pretty sure there is an option for this, holding shift makes it show the menu.
I think you can get that by setting `GRUB_TIMEOUT_STYLE=hidden` and `GRUB_TIMEOUT=0`. Then you can hold `Shift` to see the GRUB menu, otherwise it will boot the default option immediately.