I just installed the page break plugin. It appears on my CKeditor with a spellcheck icon.
See picture: ck_bug_1.png
This is because the CSS in the editor.css uses the "!important" tag, whilst the specific CSS for the button by the pagebreak plugin does not.
See picture ck_bug_css.png
The pagebreak plugin came with the correct icons, they just aren't beign loaded because of this CSS.
Any advice?
fixed by removing lines in editor.css
I found the reference to the pagebreak icon inside editor.css.
I deleted all of these lines and it worked.
Also need to delete relevant lines inside editor_gecko.css etc.
I have checked our demo page
I have checked our demo page as well as standalone CKEditor freshly downloaded from our page and they are working correctly.
This is most likely caused by CSS caching and I believe first thing you should do (before deleting entries in css files) is clearing browser’s cache. You probably know that but this isn't Ctrl+F5 which is cache refresh. What I'm talking about is e.g. http://www.wikihow.com/Clear-Your-Browser%27s-Cache
NOTE: I believe we have this issue reported and there might be some icons caching problems when you use different packages for CKEditor. I personally have not experienced any of that but have seen people reporting that icons are misplaced. Until this issue is resolved on CKEditor side, the best solution is clearing cache after upgrading.
JS caching: a total pain for a very small speed gain.
I tend to make all editing-mode javascript links with php, and include a random seed, eg:
$jslink='ckeditor.js';
$jsindex='?' . rand(1,1000);
echo "<script language='javascript' src='" . $jslink . $jsindex . "'></script>";
Relies on the fact that the browser typically treats any URL with new GET parameters as a fresh page request.
You can also do this from javascript itself, using document.write()