Our web server logs every request it serves: the time, your IP address, the country it maps to, the page or file, the referring page and your browser's user agent. Fetches of the installer and the binaries are logged the same way, with whether the download finished. The daily version check is deliberately left out of every log, because keeping it would be telemetry on the binary.
Each page also loads /a.js, a short script of our own that you can read. It reports the page you opened and the page that sent you there, the links and buttons you click, how long the page was visible and how far down you scrolled. When you copy something it reports only that a copy happened and whether it was inside a code block (and which block on the page). It never sends the text you copied. It sends that to this same server and nowhere else. It sets no cookie and stores nothing in your browser, so a visit is linked to the next one only on our side, by IP address and user agent. If your browser sends Do Not Track or Global Privacy Control, the script sends nothing.
We use this to see which pages people read and whether they went on to install. There is no third-party analytics, no advertising tracker and nothing is sold or shared. The logs are kept for 12 months and then deleted. The one third party a page load reaches is Google Fonts, which serves the typefaces and so sees your IP address. Mail security@fightclub.pro to have the log lines for your IP address removed.