I eventually discovered the Synchronize button on Thunderbird calendar, which when I click it synchronizes the two calendars, but not always.

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Hello there Turing.

Necessary plugins

There are two plugins that must be installed:

Lightning - the actual calendar plugin: https://addons.thunderbird.net/en-US/thunderbird/addon/lightning/?src=search?src=search

Provider for Google - allows bidirectional access to Google : https://addons.thunderbird.net/en-US/thunderbird/addon/provider-for-google-calendar/

Install both of these plugins, from within Thunderbird. (Menu button | Plugins | See all and then search for Lightning and then Provider for Google. Click Add to Thunderbird and then, when prompted, restart the app).

Note: you need to allow cookies from google in thunderbird. if there is a popup for this.

Once these have been installed, and Thunderbird restarted, you're ready to configure

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Hello there Turing.

Let yourself be heard if you have performed these things.

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Hello Turing.

That was to install the program.

When you create an event, check which calendar it's being added to. If it isn't being added to the Events calendar, you may not see it in the Google Calendar app or at calendar.google.com.

Open the Google Calendar app Calendar. In the bottom right, tap Create Create. Next to the Event calendar icon Event, make sure it says Event. If you don't see Event, tap the Event Calendar icon to switch to the correct calendar.

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