This extension runs only in your browser, on https://ev.flyingbluedoxie.com and in the Tesla sign-in tab it opens. Your Tesla password and codes are typed on Tesla's own page and never reach the extension or EV Logger. The extension exchanges Tesla's one-time code for tokens directly with Tesla and hands them only to the EV Logger page that asked, which stores them in your account. A sign-in in progress is kept in the browser's memory for at most 15 minutes; nothing is written to disk and nothing is sent to the extension's author or anyone else. EV Logger's full privacy notice: https://ev.flyingbluedoxie.com/privacy