This was my original tic-tac-toe project I worked on after finishing CSE154 (Web Development) at UW. You can enter any lobby and visit play against players who are in the same lobby. Only the first two players in that lobby can play and the lobbies reset after a set time (3 hours). To test this out yourself, you can join an open lobby in one tab and join the same lobby in an incognito tab to play against yourself.
Please see what I did in version 2 of this project found here