not anymore, Firefox legacy works in Mountain lion as that is streaming the euro finals now perfectly.
i'm surprised too!
Firefox Legacy isn't supported anymore AFAIK, and as mentioned the 2010 MacBook Air is slow. However, those Core 2 Duos do support hardware h.264 AVC acceleration so it's not a huge surprise it can stream video. Depends on the streaming site though, as DRM compatibility can be an issue.
Loved the 11" Air, but that 2020 i5 Air was just a dog in the end. I struggled to get 5 hours of run time out of it and was constantly babying the battery, turning down the brightness, all that dumb stuff. Then the M1 came along and got literally triple the battery life and felt twice as fast.
I must admit I did not like those 11" Airs, even when they were first launched. The screen quality was poorer than other Macs at the time. As mentioned, it was also slow, although SSD helped a lot.
I liked the Retina 12" MacBook much better, but that did have that butterfly keyboard, and it wasn't cheap. However, I waited for the 2017 though because it had a noticeably better keyboard than the 2015 model, it was much faster than the 2015 model, and the 2017 got hardware h.265 HEVC acceleration. I still use that, running Ventura.
Back in 2021, I toyed with the idea of buying a used 2020 Intel i3 Retina MacBook Air to give to the wife since its prices dropped fairly quickly after the Apple Silicon transition, but people said it ran hot with poor battery life. In the end I just picked up an 2017 i5 MacBook Air for super cheap, but will likely upgrade that to Apple Silicon when Apple releases the base MBA with 12 GB RAM. She's now starting to complain that she can't play some videos, which is because it does not support hardware h.265 HEVC acceleration. (Some of the video for our kids' recitals, etc. are recorded in h.265 format now, with no h.264 option.)
And to get back on topic, for the Mac mini, I have a 1 TB 16 GB M1 which I got for a decent price used a couple of years back, but the lack of ports still bugs me, since using a Thunderbolt 4 hub just isn't the same experience as having built-in Thunderbolt ports. I anxiously await the next Mac mini, as I'm intrigued by the knowledge that M4 has 4 Thunderbolt controllers.