Every HTML e-mail who is displayed inside the "SOGoHTMLMail-CSS-Delimiter mailer_htmlcontent" elements has its styles corrupted. But it only can be noticed on more complex HTML codes.

That happens because of the strategy addopted to avoid the Sogo's css stylesheet beeing applyed over the message's stylesheet.

To do that, the Sogo's algorithm loads all the message stylesheet files content, declared inside the HTML head and body element, and rewrite then in a single <style> tag after the class "SOGoHTMLMail-CSS-Delimiter mailer_htmlcontent", including the class "SOGoHTMLMail-CSS-Delimiter" on each one.

While sogo does that, it also rewrite every single class attribute with the "!important" tag.

But the "!important" tag does not only overwrite the past style declaration, it changes the whole next stylesheet hierachy. It means that simple HTML mails will be displayed correctely and the problem will not be noticed. But the complex ones, who has more than one stylesheet declared and anothe styles declared insite the html elements, will be corrupted.