Many documents I will write plain text file, compatible with everything more than HTML and Microsoft Word is. I also don't like WYSIWYG when I do want text formatting.
I don't use favicon on my own server, and have it disabled on the browser. I also think "Plain Text Project" uses too much CSS too. Just you can use plain text. I don't want to use your large font sizes and narrow columns.
I use file with plain text for editing. Articles on Usenet and Unusenet too, are written plain text sometimes also with headers, but the headers are also a plain text just are more structured. Some programs have a different user interface for adjusting the headers, but I just use them same as with the rest of the text.
In addition to Usenet articles, there is many other thing that you can use a plain text file for many other things. Depending what kind of data it is, you might use just one string per line, or CSV or TSV, or JSON or YAML, or RDF (RDF/XML isn't so good, but I think the RDF Turtle format is good), etc.
In many cases I wrote my own programs because I do not like the existing ones.