I printed something!

I got an email this morning with a PDF attachment. I’m still mostly using Fastmail’s web UI for email, and I downloaded the attachment. I opened the PDF and hit “Print”. Up popped a print dialog, in which both my printers were listed. I selected the laser printer, and you’ll never believe what happened next. It printed!

I have no idea how or why that worked. I didn’t add the printers manually. I didn’t muck about with drivers and whatnot. I just printed. I’m thrilled about this, honestly, but I feel like I need to know how and why it worked so easily. I’m suspicious! :)