tinymce inserting span into list tags

Question

I have some text in tinymce editor inside <p> tags, nothing else, no classes, no styles. When I select the text and click the Unordered List button, then the <p> become a list. But every <li> looks like this:

<li><span style="font-size: 12px; line-height: 1.5em;">Some text...</span></li>

Where are those styles coming from, which tinymce config option, which file, which anything ??? I want the List button to just add list html tags, without any spans and styles.

Here is my tinymce config. The config is copied directly from Chrome inspector (that's why there is no indentation in nested props): (the breakpoint was at line 13547, at statement tinymce.add(t); in tiny_mce_src.js)

settings: Object
accessibility_focus: true
accessibility_warnings: false
add_form_submit_trigger: true
add_unload_trigger: true
apply_source_formatting: 0
bodyClass: "wysiwygeditor"
button_tile_map: true
content_css: "/sites/all/themes/adaptivetheme/at_core/css/at.layout.css,/sites/all/themes/atsl/css/global.base.css,/sites/all/themes/mytheme/css/global.styles.css
convert_fonts_to_spans: 1
convert_urls: false
delta_height: 0
delta_width: 0
dialog_type: "modal"
directionality: "ltr"
doctype: "<!DOCTYPE>"
document_base_url: "/"
entities: "quot,apos,amp,lt,gt,nbsp,iexcl"
entity_encoding: "named"
extended_valid_elements: ""
fix_table_elements: true
font_size_legacy_values: "xx-small,small,medium,large,x-large,xx-large,300%"
font_size_style_values: "xx-small,x-small,small,medium,large,x-large,xx-large"
forced_root_block: "p"
formats: Object
hidden_input: true
id: "edit-body-und-0-value"
ie7_compat: true
indent: "simple"
indent_after: "p,h1,h2,h3,h4,h5,h6,blockquote,div,title,style,pre,script,td,ul,li,area,table,thead,tfoot,tbody,tr,section,article,hgroup,aside,figure,option,optgroup,datalist"
indent_before: "p,h1,h2,h3,h4,h5,h6,blockquote,div,title,style,pre,script,td,ul,li,area,table,thead,tfoot,tbody,tr,section,article,hgroup,aside,figure,option,optgroup,datalist"
indentation: "30px"
inline_styles: true
language: "en"
mode: "none"
object_resizing: true
padd_empty_editor: true
paste_auto_cleanup_on_paste: 0
plugins: "style,-codemagic"
popup_css: ""
preformatted: 1
relative_urls: true
remove_linebreaks: 1
remove_script_host: true
render_ui: true
skin: "thebigreason"
strict_loading_mode: true
style_formats: Object
submit_patch: true
table_inline_editing: false
table_styles: Array[0]
theme: "advanced"
theme_advanced_blockformats: "p,h3,h4"
theme_advanced_buttons1: "bold,italic,underline,justifyleft,justifycenter,justifyright,separator,bullist,numlist,indent,outdent"
theme_advanced_buttons2: "link,image,media,charmap,blockquote,separator,formatselect,removeformat,styleselect,codemagic"
theme_advanced_buttons3: ""
theme_advanced_resize_horizontal: 0
theme_advanced_resizing: 1
theme_advanced_resizing_use_cookie: false
theme_advanced_statusbar_location: "bottom"
theme_advanced_toolbar_align: "left"
theme_advanced_toolbar_location: "top"
url_converter: function (url, name, elm) {
url_converter_scope: tinymce.create.Editor
validate: true
verify_html: true
visual: true
width: "100%"

Where "formats" are like this:

formats: Object
aligncenter: Object
classes: "align-center"
selector: "p,h1,h2,h3,h4,h5,h6,td,th,div,ul,ol,li,table,img"
__proto__: Object
alignleft: Object
classes: "align-left"
selector: "p,h1,h2,h3,h4,h5,h6,td,th,div,ul,ol,li,table,img"
__proto__: Object
alignright: Object
classes: "align-right"
selector: "p,h1,h2,h3,h4,h5,h6,td,th,div,ul,ol,li,table,img"
__proto__: Object
forecolor: Object
classes: "forecolor"
inline: "span"
styles: Object
__proto__: Object
hilitecolor: Object
classes: "hilitecolor"
inline: "span"
styles: Object
__proto__: Object
strikethrough: Object
inline: "line-through"
__proto__: Object
underline: Object
classes: "underline"
exact: true
inline: "span"
__proto__: Object
__proto__: Object

"Style formats" are like this:

style_formats: Object
blink: Object
attributes: Object
class: "blink"
__proto__: Object
inline: "span"
title: "Blink"
__proto__: Object
__proto__: Object

Answer 1

Looks like i found a solution to your problem: http://martinsikora.com/how-to-make-tinymce-to-output-clean-html

The key lies in using extended_valid_elements. This will remove all spans without a class attribute

extended_valid_elements : "span[!class]"

Answer 2

My tinymce config was missing the 'plugins' setting, as compared to http://fiddle.tinymce.com When I added the 'plugins' setting, tinymce no longer inserts spans with styles to lists.

Some additional information that led me to the solution:

line 14212 of tiny_mce_src.js was returning false when debugged on my website (while creating the list) - and it returns true on tinymce fiddle. ( if (o = t.execCommands[cmd]) {.....)

somehow on my website tinymce performed line 15063 (execNativeCommand function) while on tinymce fiddle it did not (perhaps the result of missing plugins)

native Chrome execCommand has problems with inserting styled spans as described here: http://help.dottoro.com/ljcvtcaw.php and I also created a fiddle to confirm it: http://jsfiddle.net/fUsmx/ (close and reopen inspector to see the result)