I hope that this isn't a stupid question.
I have a fairly modern machine (c. 2021) which is an AMD 8 core, 16 GB PC. It came with Windows 10 installed.
The first thing that I did was to set it up to dual boot Ubuntu. To do this, I had to tell the UEFI / Bios that I wanted it to behave as a "legacy" machine and ignore "Safe Boot". This was all fine and I've got Ubuntu doing everything that I could ask of it. Currently I'm on Ubuntu 22.04.4 LTS.
When I fire up the machine, I get a Windows boot loader which asks me if I want Linux, Windows 10 or Windows 7 (ignore the last option, it doesn't work well: it's an OS from an older PC that I sort-of rescued: I never use it). If I pick Linux it starts up (I think) Grub 2- and from there I can start up Ubuntu.
All happy. All working. The system does what I want.
BUT. I hear that Microsoft is going to stop supporting Windows 10 next year, and I have a couple of applications, which only run under Windows.... To "upgrade" to Windows 11 I'll need to re-enable full UEFI and Safe Boot.
My question is: will I lose access to my Linux system? If I do, how can I get it back? I don't want to format my Linux drives and partitions and reinstall: it's taken a long time to get the system working exactly the way that I want.
All help and advice gratefully received.
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