There were a few things (GDI handles and suchlike) that had very small limits. Once you exhausted them, the system was basically unusable. There was a little program you could run that would show the number allocated vs allowed. By the time you'd launched one program, they were normally 60-90% gone.

These two are related. OS/2 needed 16MB of RAM to be useable back when I had a 386 that couldn't take more than 5MB (1MB soldered onto the board, 4x1MB matched SIMMs). Windows NT had the same problem - NT4 needed 32MB as an absolute minimum when Windows 95 could happily run in 16 and unhappily run in 8 (and allegedly run in 4MB, but I tried that once and it really wasn't a good idea). The advantage that Windows NT had was that it used pretty much the same APIs as Windows 95 (except DirectX, until later), so the kinds of users who were willing to pay the extra costs could still run the same programs as the ones that weren't.

I never ran 3.0 on a 386 to try that. On Windows 3.1 it wouldn't work, because the OS required either (286) protected mode or (386) enhanced mode. Running 3.0 on a 386, the DOS prompt would use VM86 mode (yes, x86 has had virtualisation support for a long time, but only for 16-bit programs). Windows 3.0 could run in real mode, so would work inside VM86 mode. In real mode, it didn't have access to VM86 mode (no nested virtualisation), so probably couldn't start again.

I'm not sure if it ever became a real product, but the Novell guys did have Netware running as a paravirtualised Xen guest. Apparently it was quite an interesting challenge, as Netware was one of the few operating systems to use rings 1 and 2 on i386.

And Windows 3.1 lost real mode support. You could run Windows 3.0 on an 8086 with an EGA screen and 640KB of RAM (I did - the machine originally shipped with GEM). I think 3.1 still have 286 protected mode support, but didn't work very well unless you ran it in 386 enhanced mode. It was a bit sad that the version of Windows that required an MMU didn't use it to implement memory protection...

Sort of. The desire not to cannibalise sales was a key factor in the design of the PC, but these were also features that IBM didn't think would be missed.

IBM knew what multitasking was for: it was to allow multiple users to use the same computer with administrator-controled priorities. Protected memory was for the same things. Why would you need these on a computer that was intended for a single user to use? A single user can obviously only run one program at a time (they only have one set of eyes and hands) and you can save a lot in hardware (and software) if you remove the ability to do more. And, of course, then no one will start buying the cheap PCs and hooking them up to a load of terminals rather than buying a minicomputer or mainframe.

My father's company got their first Windows 3.0 install because they bought a diagram tool (Meta Design, I think), that came with a free copy. The company that made it had decided that bundling a copy of Windows 3.0 was cheaper than writing (or licensing) a graphical toolkit for DOS and an associated set of printer drivers. I don't know if they were the only company to do this, but after a year or so they stopped bundling Windows and just expected their customers to either have a copy already or go and buy one.

Win 3.x would pre-emptively multitask DOS windows if you had a 386. It was one of its touted features. (There may have been a setting to turn this off and on, it may have been off by default). Personally during this period I used DESQview (or however it was capitalized) as a multitasker.

Windows 3.0/3.1 would pre-emptively multitask DOS windows if running on an 80386.

So did the Acorn Archimedes (the computer the ARM CPU was originally made for). RiscOS even had things like anti-aliased fonts by then, and certain user interface concepts that didn't show up elsewhere until Mac OSX came out.

However, the PC and Microsoft was already massively entrenched, and the news was huge - finally the computers most people actually used at work were going to catch up with the Mac, Amiga, Archimedes and other machines.

But anyone could tell that Windows was going to be huge. The PC was already dominant and Microsoft was already nearing monopoly position in the PC market (and IBM compatibles at the time had fallen in price such that they were price competitive with the Amiga) and the upgrade path for most people was not to buy a whole new computer but just add Windows.

I remember the news at the time. It was huge. Finally, the PC that nearly everyone was using was catching up to the Mac, Archimedes, Amiga etc.

You're wrong, unless you can provide equally large-scale, cross-platform metrics. Compare the iOS 8 (most popular iOS version with about 85% usage share) crash rates (most recently 2.05%) with KitKat 4.4 (60% share) at 2.53% crash rate.

Configurability is slowly being removed. Remember how configurable the UI used to be before the Australis disaster hit?

Those comments started out as constructive criticism. However, Mozilla pressed on with their determination to ignore and alienate users.

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Now Mozilla is getting the criticism they have earned.

Mozilla/Firefox has a problem. A big one. The first step in solving a problem is to identify its cause and not, as you attempt, to blame others for Mozilla's self-inflicted problems.

The problem there is that you're using Windows 8. Get a real OS, not one with a toy interface.