when messages are imported from the the other email accounts such as yahoo or fastmail are the messages erased from those accounts or do they remain there?
i am thinking about setting up a thunderbird account and want to link it to 3 other email accounts. i want to import the old emails from these accounts but i do not want them erased from the original accounts. 1. does thunderbird automatically import and erase the old emails? 2. do new emails remain on the original sites or do they "disappear" to thunderbird?
Alla svar (1)
1. does thunderbird automatically import and erase the old emails?
Setting up an existing account in Thunderbird is just like adding another method to access messages for this account. There isn't any import.
Wrt 'erase' old messages, if you mean that messages are removed from the server, this can happen, depending on how you setup your account.
In general, with POP messages are removed from the server by default. With IMAP all messages are managed on the server.
Choose the account type that fits your needs when setting up the account in Thunderbird.
2. do new emails remain on the original sites or do they "disappear" to thunderbird?
See above.