@scottalanmiller is correct, those numbers are produced on the fly based on active websocket sessions, and not stored anywhere.
However, you might be interested inGitHub - barisusakli/nodebb-plugin-browsing-users: Adds browsing users to topics
Adds browsing users to topics. Contribute to barisusakli/nodebb-plugin-browsing-users development by creating an account on GitHub.favicon
GitHub (github.com), which brings a live-list of current users in-topic back to topic.tpl 😄