One idea is to uninstall the grub package in Ubuntu.
Though I don’t know if some Ubuntu update will re-install grub again, as I’m not using Ubuntu.
But whatever you do, make sure you create a good backup of your personal data, just in case everything goes south.
A bit outside of this boy’s skillset, I think. I think it’ll be sufficient to just make the tweak in the BIOS settings, now that I’m familiar with that process.
Good advice for anyone on any OS. That said, as I come upon the 1 year anniversary of my foray into Linux, in spite of the fact that I now have all 3 of my laptops running various distros of Linux (and, yeah, I’ve done a fair bit of hopping with them!), my “mother ship” – the device I run in my home office 15 hours a day 7 days a week – continues to be my Windows 10 PC.
There is nothing in any of the Linux distros I run that I consider all that important or hard to replace. Any work-related files that are created on the Linux laptops are saved off to a USB and in 99% of the cases were also sent off to a client or an associate. As far as app profiles go, there are basically 3 apps I always install (and 2 apps I always UN-install if they’re present) and 2 of those have online profiles.
All of this led me to decide early on that Timeshift or any other type of rollback is just not worth the space they take…because I could do a fresh install in very little additional time. Not only that but I’ve got some online friends who report quite the failure rate with those backup packages. So, there you are…FWIW.