I experienced the same bug in Thunderbird 60.4.0 (64-bit, Ubuntu 18.04.1 LTS x86_64) yesterday. The only way how to send an email was adding the recipient in local address book.
After clicking on Send button, Thunderbird in safe mode reported 'JavaScript error: chrome://messenger/content/messengercompose/MsgComposeCommands.js, line 5656: NS_ERROR_NOT_IMPLEMENTED: Component returned failure code: 0x80004001 (NS_ERROR_NOT_IMPLEMENTED) [nsIMsgCompose.expandMailingLists]'.
I had to change ldap_2.servers.history.filename' preference (history.mab file changed to new history2.mab file) as suggested by Edoardo Tirtarahardja to be able to send an email.
I experienced the same bug in Thunderbird 60.4.0 (64-bit, Ubuntu 18.04.1 LTS x86_64) yesterday. The only way how to send an email was adding the recipient in local address book.
After clicking on Send button, Thunderbird in safe mode reported 'JavaScript error: chrome: //messenger/ content/ messengercompos e/MsgComposeCom mands.js, line 5656: NS_ERROR_ NOT_IMPLEMENTED : Component returned failure code: 0x80004001 (NS_ERROR_ NOT_IMPLEMENTED ) [nsIMsgCompose. expandMailingLi sts]'.
I had to change ldap_2. servers. history. filename' preference (history.mab file changed to new history2.mab file) as suggested by Edoardo Tirtarahardja to be able to send an email.