Simple website that displays all players connected to a selected server. Available here: https://igorovh.github.io/fivem-player-list/
It uses the FiveM endpoint, which is also used in their UI:
https://servers-frontend.fivem.net/api/servers/single/serverId
Visit the FiveM Server Browser and click on your chosen server.
Then look at the URL and copy the last fragment, which is the Server ID. Example:
https://servers.fivem.net/servers/detail/vp4rxq -> vp4rxq
Find the server in the FiveM client and click on it.
On the right side you will see a "join URL", where the last fragment is the Server ID. Example:
cfx.re/join/vp4rxq -> vp4rxq
