More often than not, the details that make your device unique on one day will not stay unique by day two. Your browser might change versions, you might resize your viewport, install a font, etc.
I believe phone apps can get more conclusive device IDs via the SDK, but for web traffic cookies and IP addresses are still the only reliable identifiers. I would take any study or hypothetical about fingerprinting with a massive grain of salt if they don't keep a stable match for 30 days.
It routes you to a chat room based on your browser fingerprint. You can check back every so often and see that your room has changed. If your hardware/fingerprint is generic enough, you’ll see other people’s messages in “your” room.