Blocks

This is a bug,

In blocks/index.php on line 360
if (mimeinfo("type", $file) == "text/html") {
                $usehtmleditor = can_use_html_editor();
} else {
                    $usehtmleditor = false;
}

$usehtmleditor = false;    // Always keep it off for now

Never use an html editor. I'm comment this last line.