etherpad-lite/doc/cookies.md

Cookies

Cookies used by Etherpad.

Name	Sample value	Domain	Path	Expires/max-age	Http-only	Secure	Usage description
express_sid	s%3A7yCNjRmTW8ylGQ53I2IhOwYF9...	example.org	/	Session	true	true	Session ID of the Express web framework. When Etherpad is behind a reverse proxy, and an administrator wants to use session stickiness, he may use this cookie. If you are behind a reverse proxy, please remember to set trustProxy: true in settings.json. Set in webaccess.js#L131.
language	en	example.org	/	Session	false	true	The language of the UI (e.g.: en-GB, it). Set in pad_editor.js#L111.
prefs / prefsHttp	%7B%22epThemesExtTheme%22...	example.org	/p	year 3000	false	true	Client-side preferences (e.g.: font family, chat always visible, show authorship colors, ...). Set in pad_cookie.js#L49. prefs is used if Etherpad is accessed over HTTPS, prefsHttp if accessed over HTTP. For more info see https://github.com/ether/etherpad-lite/issues/3179.
token	t.tFzkihhhBf4xKEpCK3PU	example.org	/	60 days	false	true	A random token representing the author, of the form t.randomstring_of_lenght_20. The random string is generated by the client, at (pad.js#L55-L66). This cookie is always set by the client (at pad.js#L153-L158) without any solicitation from the server. It is used for all the pads accessed via the web UI (not used for the HTTP API). On the server side, its value is accessed at SecurityManager.js#L33.

For more info, visit the related discussion at https://github.com/ether/etherpad-lite/issues/3563.