<p>&nbsp;</p> inserted unexpectedly

[moriya9n]

Steps to reproduce

1. download ckeditor_4.5.1_full and expand
2. set config.js as follows:

CKEDITOR.editorConfig = function( config ) {

config.allowedContent = true;

};

3. open index.html
4. change source view (push source button)
5. delete all text
6. insert following text

<marquee>test</marquee>

7. change html view (push source button)
8. change source view (push source button)
9. :

Expected result

<p>&nbsp;</p> are not expected

Actual result

<p>&nbsp;</p> are inserted unexpectedly

Other details (browser, OS, CKEditor version, installed plugins)

ie 11.0.9600.17959 (japanese) os window 7 professional service pack 1 ckeditor_4.5.1_full no plugins installed

[Piotrek Koszuliński]

There's no marquee element in HTML anymore. If you want to use it, then you need to extend CKEditor's DTD (CKEDITOR.DTD) so CKEditor understands what is it that element and where it can be placed.

[moriya9n]

Any invalid HTML tag with allowedContent = true settings looks to keep generating <p>&nbsp;</p>. Is it OK?

[Piotrek Koszuliński]

There's no rule what invalid tag may or may not generate. Invalid tag is invalid, so whatever happens is reasonable (well... except crashing and losing data).