New kernel installed but does not shown in grub

[Antynea]

@omano

//EDIT: anyway, the fact that your grub.cfg file is not updated and you have a leftover grub.cfg.new file shows that something breaks during the update-grub process apparently. Now the thing is to find what breaks and fix it.

Hello,
grub-btrfs 4.10 break grub-mkconfig
grub-btrfs 4.10.2 solved this.
Sorry for the inconvenience.