Why. I write these posts in my own time, and I want to know which ones actually help: which get read to the end, where people give up halfway, and which topics bring readers from other sites. That decides what I write next, which old posts I update or fix, and where a follow-up is worth it.

What. When you leave a post, your browser sends one anonymous message: which post, how far down you got, how long the post was on your screen and how much of that you were actively reading, and which site linked you here. No cookie, no ID, no IP address, no device details, so visits can't be linked to you or to each other. Stored in the EU; only I see it.

Off means this browser sends nothing. Browsers that send Global Privacy Control or Do Not Track are excluded automatically. Privacy details