Slackware in 1998 I think, from a cd that came in a book I bought while in university.
It didn’t stick, but it demystified it and I’ve used a lot of flavours of *nix since then.
I remember not being able to get sound to work at all on my pentium computer.
Adding to this, but I’m also not aware of many great Product Managers, UX designers or UX writers contributing to FOSS. Many devs have worked with shitty PM’s and like to dismiss their value, but a great one can make a massive difference in the quality of a product.
Same with the extensive UX design and UX testing that goes into making great products.