Troubleshooting sSMTP: Authorization failed

My requirements are: * send an email from the terminal (for the sake of batch processing) * attach a pdf file to that email (the pdfs would be identical for all recipients, except for a watermark) * specify a reply-to address (myusername@gmail.com) I've tried the "simplest answer to sending one-line messages via gmail is to use ssmtp" , and several variants, and keep getting: > laptop sSMTP: Authorization failed (535 5.7.8 > https://support.google.com/mail/?p=BadCredentials d13sm3920147qkj.27 - > gsmtp) Google settings: * IMAP enabled * Allow less secure apps is ON For each ssmtp.conf setup that I tried, I have done DisplayUnlockCaptcha just before: $echo "Testing...1...2...3" | ssmtp myusername@gmail.com Looking at the stated thread alone, there is no consensus as to how /etc/ssmtp/ssmtp.conf should be set up: * mailhub=smtp.gmail.com:587 vs 465 * UseTLS=YES vs UseSTARTTLS=Yes (or both?) * hostname=localhost vs whatever was put there as the default (in my case, laptop) Could someone make a suggestion to sort this out, and possibly paste in full a working conf file? There is a claim in a thread from 2017 , that: > You can not use external applications with your normal password, you > must go to https://security.google.com/settings/security/apppasswords Is that the case? (I'm not able to do it) What alternatives are there? PS: * OS: Linux Mint 19 Tara * ssmtp was tested from a clean install preceded by upgrade/update * a couple of years ago, I was a able to send emails using the same OS (earlier version) * To make sure the value of AuthPass is correct, I used it to manually log into my google account.