The chromium browser on steam is based on version 47, a vulnerable and out of date version.
http://www.ghacks.net/2016/02/08/steam-uses-insecure-out-of-date-chromium-browser/
Even when visiting google pages it advises to upgrade the browser because of security problems...
Nothing extracted yet.
The chromium browser on steam is based on version 47, a vulnerable and out of date version.