looking for open-source SDI (single-document interface, i.e. no document tabs) plain text editor that has text encoding indicator/switcher in some prominent place in its UI, like on toolbar or status bar
also desirable:
1) code folding for any text indented with Tab characters (code folding for relaxed lexer of YAML language can do this, for example notepad++ does it), code folding for text indented with whitespaces may be Ok too
1a) also would like folded segments of text to look like in Eclipse and MS Visual Studio, i.e. one line of text encased into rectangle and indented to same degree as first line of folded segment of text, ability to see contents of folded text segment in tooltip is very welcome as well
2) binary-portable (portable in portableapps.com meaning)
3) no dependencies like .NET, Java etc
4) recognition for both windows and unix end-of-line characters
5) having both windows and linux binaries is welcome
please do not offer notepad++ unless you know how to remove tabs from it (as opposed to just hiding the tab bar)
EDIT: another desirable property: UI without deliberately sharpened corners (without windows 10 style of GUI)