Re: [Trisquel-users] Why Security Experts Are Using an Ancient Email Format in 2015

[tomlukeywood]

Just looked at the wikipedia page and found a very good reason not to use  
HTML in email

If an email contains web bugs (inline content from an external server, such  
as a picture), the server can alert a third party that the email has been  
opened. This is a potential privacy risk, revealing that an email address is  
real (so that it can be targeted in the future) and revealing when the  
message was read. For this reason, some email clients do not load external  
images until requested to by the user.