Tor Browser sessions accumulate state over time. Cookies (locally), history, cached DOM state. None of this is inherently dangerous, but a long-lived session is a longer window for anything to go wrong.
The habits
Close Tor Browser after each WeTheNorth session. Open it fresh when you need it again.
Use New Identity between accounts. If you have more than one WeTheNorth account (buyer account and separate research account, for example), switch identities between them.
Do not leave Tor Browser open for days. The longer the session, the more state accumulates, the higher the chance something crosses.
Why this matters
Small habit. Small effect. But operational security is the sum of many small habits. Skipping one is fine. Skipping many is how accounts get compromised.