How to make reconnect after send X amount o emails

[unluko]

Hi,
i have a problem sending emails with thunderbird , idk there is some software that are older than thunderbird have this options and i cant find it in thunderbird
my question is there is an addons or an options to make thunderbird close connection to smtp after sending like 20 emails and then open connection again and send 20 ....etc to prevent server overloading
example from an old software : https://prnt.sc/sehpze
so i can send 10 emails per connection then reconnect and send 10 emails
can u please help me

[makaiguy]

Are these broadcasts of same message (even if custom fields are replaced in each copy)? Look at tbe Mailmerge add-on. You can't send in batches, but you can set a delay between individual messages that accomplishes the same thing.

[unluko]

Are these broadcasts of same message (even if custom fields are replaced in each copy)? Look at tbe Mailmerge add-on. You can't send in batches, but you can set a delay between individual messages that accomplishes the same thing.

ty for responding
i ve already tried mailmerge , i dont want dealy between 1 message to another .. i want to like send email to 20 recipients pause and send another 20 . so its keep open connection to smtp server and close it every 20 recipients