The initial idea for this site is to let people more easily share FFXIV character names when playing with Twitch streamers.
If you want others in Twitch chat to see your character name, sign in and set it.
If you want to see the names of others, installing the browser extension is necessary.
You can delete your info at any time.
If you've set your info, updated it, or deleted it, there can be a few minutes before cached data is updated.
A force-refresh of the browser tab can possibly help, or even a browser restart.
Be sure to check if the installed browser extension has permissions enabled for twitch.tv domains.