Thunderbird Sync

Thunderbird is an email client. It connects to your Email Service Provider ( for Example Gmail ) that you choose to use and downloads email from Gmail to Thunderbird on your device ( PC, Smart Phone ). There are 2 types for connections or Server : IMAP and POP. When IMAP is configured "everything" that you do to your emails with Thunderbird will be synchronized to your Gmail server and Vice versa. Example if you delete an email of your Gmail account using Thunderbird, that email will also be deleted from Gmail server. If you delete an email from your Gmail account using web browser, that same email will also be deleted from Thunderbird locally. If you don't want that type of synchronization then you should choose POP server ( or Connection ). To have more details I suggest that take a look at : https://support.mozilla.org/en-US/products/thunderbird https://support.mozilla.org/en-US/products/thunderbird/settings https://support.mozilla.org/en-US/kb/imap-synchronization https://support.mozilla.org/en-US/kb/difference-between-imap-and-pop3