Fire up your email client, and add your Gmail account (doesn’t matter if it’s IMAP or a Google-specific connection method, just don’t use POP3 or webmail). Control-A to select all messages in a folder. Drag and drop them somewhere else.
Source: I did this years ago when I left Google for self-hosted email. Moved all my messages into Thunderbird. Tested backups. Never looked back.
Fire up your email client, and add your Gmail account (doesn’t matter if it’s IMAP or a Google-specific connection method, just don’t use POP3 or webmail). Control-A to select all messages in a folder. Drag and drop them somewhere else.
Source: I did this years ago when I left Google for self-hosted email. Moved all my messages into Thunderbird. Tested backups. Never looked back.