Thunderbird
add new @ucsd.edu Google acount: https://support.ucsd.edu/its?id=kb_article_view&sysparm_article=KB0031939&sys_kb_id=f4a8e4461bd03410506f64e8624bcb4bÂ
remove account from Thunderbird: https://support.mozilla.org/en-US/questions/1155512
Mac Mail
add more email accounts to Mac Mail: https://support.apple.com/guide/mail/add-email-accounts-mail35803/mac
remove accounts from Mac Mail: https://support.apple.com/guide/mail/remove-or-temporarily-turn-off-email-accounts-mlhl9eb9408c
updated 02-08-2023