After logging into https://opensea.io with metamask I see that they have a log out functionality.
After some research, I realized that the "log out" is just a change in UI as I'm still connected to metamask and can only disconnect if I do so manually using the metamask chrome extension.
However, after I log in to opensea using wallectconnect with my mobile phone using a wallet app like dcentwallet, I see that my app shows that I am logged in and I have an option to disconnect manually using the app. However, if I log out using opensea, I disconnect from my wallet app.
So I assume that opensea is using some kind of event to force my app to disconnect from its site. I assume it's not a web3 event because I'm not asked for my signature when I log out of opensea and it forcibly disconnects me from my wallet app. Does anyone know what technique opensea is using to disconnect mobile wallet apps connected via walletconnect?