Substantial elements of an email client are
- the viewer,
- the editor,
and naturally all the elements that work below the surface as socket functions that enables a program to act on the internet.
The ReSecCo viewer is, not modified by me, the html viewer that is supervised by Bernd Gabriel. It is open source software and will be optimized permanently.
If ReSecCo does not display emails correctly it's mostly my fault. ReSecCo might not have decoded correctly or I disregarded a rule. Please consider that a viewer is not a matured browser. Under aspects of security this is necessary. If an author of a message uses sophisticated active content he overshoots acceptable policies. An email should be a message, not more and not less. If you want to communicate a presentation prepare a link to it. I recommend not to follow "if the content is not displayed correctly..." links if you have not identified the sender. As I recommend signing emails I recommend exclusively use auf https:// sites.
The editor (authoring tool). I have built it and therefore it may be more faulty than the tools I got from other programmers. You will use the editor to author the mails you intend to send. It is based on RTF (Rich Text Format) developed and improved by Microsoft. Meanwhile Microsoft slides RTF but it is still a mighty tool to fulfill text formatting. The Editor mostly presents a wysiwyg (what you see is what you get) view. If you have finished creation of your text ReSecCo will transform it to html/css format. This is the format email clients can display. The view within an viewer or browser mostly will be similar to the view you have had while creating the text, but not exactly. To invoke formatting of a text you may use the toolbar, keyboarded entries or the context menu. To make the toolbars appearing click into the marginal areas of the editor. The best way to become acquainted with this tool is trial.
The viewer is specialized in displaying html formatted messages. If it has to display plain text ReSecCo transforms these messages to html to simplify word wrapping and invocation of links.