The average user can’t do that in T-Bird it takes a programmer. In WLM, you can easily eliminate that header.
Step 2 - Create a new Calendar Right click on an existing calendar and select New Calendar. Open Thunderbird and click the Calendar tab at the top of the screen, or click the calendar icon to the right.
Gmail makes it easy to not only access your emails, but also connect to any of the Google apps or platforms, such as Google Docs, Drive, Google Calendar, and so on. Because if you, Ben, connect to Gmail from Thunderbird with cookies disabled then either you already have a Google cookie (LogicDaemon’s comment above : “Cookies used during web phase of oAuth2 login, which is only once unless you (or Google) withdraws token.