Here is how the plugin uses the user data from the Google account:
1. The plugin periodically queries the contacts of the Google account
2. When the user uses the address completion feature in Claws Mail, the
plugin adds the contacts from the Google account query to the
3. When Claws Mail is shut down, the plugin stores the latest Google
contacts information in a cache file in the Claws Mail config
folder. This cache file is used when the application is started again
until the first query to the Google servers could be performed.