If you are a Linux user, chances are that you are dual booting; and not because you need Office 365 or because Win 10, after all, is not so bad nowadays. No, the real reason is that more than half of your steam library still does not work in tour Ubuntu. And yes: Gimp is great (only after you spent 2 days looking for the Crop menu Item) and while Darktable and RawTherapee are really respectable (especially the latter), you will need sooner to pay Adobe a with a not neglectable part of your soul to use Lightroom because it is the only one that integrates decently with Nik Collection and it does not fry your CPU to run decently... or simply you need ACDSee to organize properly you pictures.
Well in that case (phew thank god you don't need Visual Studio... or do you?) you are going to spend the rest of your life dual booting...
Grub was a mess; Grub2 they say is better; I don't know but if you, like me, end up with 30 different kernels with several patches for stuff you don't even remember or even worst you discover ukuu (yeah thanks Tony... you made all the kernel super easily installable on ubuntu and now I have 200 different kernels in GRUB)...
Well, you are lost maybe you just need to set a default but then you need to change it again and then not and then again. Your life at that point is miserable. I understand you.
But thanks to GRUB2 and to its impossible-to-find documentation you can now save your latest grub selection for the next boot so you can finally leave your PC booting un-attended (yes... in 2020 your dual boot computer can finally boot unattended!!)
You just have to edit 2 lines of
/etc/default/grub with this 2 stupid variables:
and then don't forget to run
And your life finally will change... for the better
If you keep in booting in the wrong kernel, repeatedly, not even this will help you. It's too late by then.