UI color plugin fails in IE with 3+ editors

[highjinx_53]

With three or more editors in the same page in IE, trying to change the UI color for all editors causes a JS exception when changing the color for the third editor.

The specific problem is in skins/kama/skin.js, line 153: uiStyle.$.styleSheet is null.

[arczi]

I was unable to reproduce this bug (IE7 and 8). Could you provide more information?

[fredck]

You may attach a test page for it, including the precise steps to be taken to reproduce it.

[pomu0325]

Try with html which has a lot of <style> elements. kama skin seems to add <style> element during initialization, when it reaches 30, the 'uiStyle.$.styleSheet is null' error occurs.

refer:  All style tags after the first 30 style tags on an HTML page are not applied in Internet Explorer

[pomu0325]

Here is the way to reproduce this bug with CKEditor 3.0.1 sample.

• Enable uiColor in default config.js

  config.uiColor = '#AADC6E';
  

• Open CKEditor samples page with IE, and go to 'Create and destroy editor instances for Ajax applications'
• Repeat 'Create' and 'Remove' editor for 30 times
• After 30 times of clicking, '$.styleSheet is null.' error will occur

If you inspect DOM tree at this time, you can see redundant of <style id="cke_ui_color"> elements. I'll attach a possible patch to remove these <style> tags on editor destroy.

[fredck]

@pomu0325, thanks for the patch. It's wonderful to have simple solutions for issues like that.

We could go ahead with this patch idea for now, but I was wondering if we would not be able to instead reuse a single <style> element for all editors. In this way we can also make it work with a page with more than 30 editors on it (crazy thing, I know, but just in case).

[garry.yao]

Manual TCs added at :  http://ckeditor.t/tt/3912/1.html

[garry.yao]

Attaching a new patch following Fred's idea inspired by pomu0325.

P.S. You'll be regret about not seeing this TC.

[garry.yao]

Fixed with [4519].