My iMac is 11 years old. It’s unsupported by the last 4 releases of OS X for x86. I put Ubuntu 26.04 on it last night. It is dual-booting with macOS 15.7.7 Sequoia (thanks to OCLP).
(iMac Retina 27", Late 2015. Quad Core i7, 32GB RAM, 1TB NVMe main disk, 8TB HDD secondary drive. Second screen, Apple 27" Thunderbolt Display, connected over dedicated Thunderbolt cable.)
On the main machine Ubuntu 26.04 (GNOME) is fast and stable. Wifi, audio, power management, screen resolution, all working.
But when I connect my 2nd screen, an Apple 27" Thunderbolt Display, it freezes for several minutes. The 2nd screen lights up but the primary blanks. USB stops responding. Even if I disconnect it, I can’t shut down cleanly.
On an old Dell XPS13 laptop with Thunderbolt 3, through a Startech Thunderbolt 3-to-Thunderbolt 1 convertor, the display works fine in Pop OS 24.04, but only as a screen: its USB, audio, webcam, Ethernet and Firewire ports are not detected.
This seems a serious incompatibility issue: an Apple display with an Apple screen.
