You could use something like lieer[1] which will also sync your notmuch tags with gmail labels.
If you don't want to sync the labels, I'm sure there are plenty of solutions out there to download Gmail to your local machine in a well known format like Maildir.
You could use something like lieer[1] which will also sync your notmuch tags with gmail labels.
If you don't want to sync the labels, I'm sure there are plenty of solutions out there to download Gmail to your local machine in a well known format like Maildir.
[1] https://github.com/gauteh/lieer