Read preferences from DOM initialData rather than API?

[maxpatiiuk]

Google Calendar DOM has a JSON element with id initialdata, that is a treasure trove of data:

• user preferences: customCalMode, defaultCalMode, weekStart, format24HourTime, locale, hideWeekends
  • don't need to get these from the API
• user calendars
  • don't need to get these from the API
  • that combined with Consider scrapping data from webpage for current week rather than doing API request #234, means we won't need to require sign in until we need to visualize month/year data (though reading from the DOM would be more fragile)
• initial events (but only for Main and Family calendars?)