(ShowStopper) Emails sent through Vivaldi are rejected today with some SMTP DATA/BDAT command error

[lavanyadeepak]

GMX/Mail.com outright rejected the message
Outlook/Office365 accepted initially but later returned back the email through its postmaster

Update as of 06:03 AM Eastern Time on 11th August 2022:

Just observed that more number of email providers have started rejecting with the same message through #Vivaldi.

Error from SMTP server:

Remote Server returned '550 5.6.11 SMTPSEND.BareLinefeedsAreIllegal; message contains bare linefeeds, which cannot be sent via DATA and receiving system does not support BDAT'