[rounce]

What’s with the weird abbreviations?

[kwanbix]

He is saving 4 keystrokes out of ~400 by typing LNX instead of Linux.

[freedomben]

But holding the shift key makes up for it, so seems like a bad strategy

[dainank]

You are overthinking it. It is neither a strategy nor keystroke saving (although technically with shift its 4 keystrokes as opposed to 5 for Linux and quite a few saved for Windows). I just typed that without thinking probably because it looks better and reads a bit easier (subjectively).