> The Linux support for software suspend/hibernation was really flaky at the time, but it worked perfectly on Apple hardware, because all Linux had to do was to tell the hardware "do the suspend thing now" (IIRC by tweaking a file in /proc).

That's interesting to read, because I ran Linux on a Macbook Pro for a few years around 2012 and the only thing on that machine that _never_ worked right was suspend and resume.