XNU/Darwin

Darwins kernel and core libraries are open source and derived from NextSTEP while the user mode APIs and GUI subsystems are all proprietary. The open source shit has been reimplemented just fine, it’s just the proprietary Apple-specific bits that have been slow to implement. Luckily the Darwin side is still being maintained by Apple even if it is only available as source code

Jailbreak and install Quasar from Cydia modern iPads with modern iOS versions have native windowed multitasking as well out of the box

You guys talk too much about what you think is, but don't go after any source whatsoever.
Here's a more technical view about XNU:
osxbook.com/book/bonus/ancient/whatismacosx/arch_xnu.html

A highlight:
So XNU is a monolithic kernel with some micro kernel abstraction built-in. There's no such a thing as a hybrid kernel. Either is Monolithic or micro.

BSDs role in XNU is greatly oversold. They can rewrite the sockets and IPC related shit from scratch and the rest of the system wouldn’t care or notice let along the programmer
The problem with this sentiment Linus is it really makes no sense calling XNU a monolithic kernel. Following the same logic you really can’t say microkernels exist either. All kernels are ‘monolithic’ to a degree

I've already jailbroken, but apt repos for my version seem to be dead. Guess I have to host one myself and compile everything.

Have anyone tried this? How you know this statement is true?

A micro-kernel is a kernel that you get by removing all non essential features, if you remove anything else, the system falls apart.
For instance, SeL4 is, basically is:
sel4.systems/Info/Docs/seL4-manual-latest.pdf
So, clearly XNU is not a microkernel, but a monolithic one with microkernel-like facilities.

That is subjective. You can say the same thing about Linux on certain distros. To me the difference between microkernels and monolithic is down to kernel-level modularity. Generally speaking the core components of Linux are tied down by dependencies to the point kernel modules have to be tied to specific kernel versions. Microkernels generally don't have issues like that, so in that sense I think XNU counts as a microkernel

Yeah there is still a tweak for iOS11-iOS12 and it's called MilkyWay. Looks almost exactly like your pic

Doesn’t iOS 12 on iPad already have native multiwindowed multitasking?

No idea. I don't own an iPad. Just an iPhone XS Max right now. And that tweak is what I use.

It's called hybrid kernel, retard.