[kbolino]

Notably, the DOS environment under Windows is running in a hardware mode called "virtual 8086 mode" which allows it to be isolated from the other DOS environments and, even more importantly, from full BIOS access. These limitations kept the whole system safer and more stable than DOS in "real mode" but made some DOS programs unusable under Windows.

[rasz]

Almost fully isolated. As far as I know Intel screwed 386 design forgetting about trapping POPF on interrupt flag change. https://devblogs.microsoft.com/oldnewthing/20160411-00/?p=93... https://docs.oracle.com/en/virtualization/virtualbox/6.0/adm...