Button icons for CKEditor 4.3 are not showing up

#2128539: Missing toolbar buttons is for the standalone CKEditor module, and there have been other similar reports from non-Drupal integrations, confirming this isn't specific to Wysiwyg module.

See http://stackoverflow.com/questions/14814159/ckeditor-missing-toolbar-icons and http://ckeditor.com/forums/CKEditor/many-icons-missing-but-functionality... for a few other occurances.

I've gotten similar issues only on a few rare occasions, so I'm unable to repeatedly reproduce it in an easy way. When I tried to debug the CKEditor theme, the Developer tools told me the buttons are using the correct offset positions for the icon sprite image, but the wrong (or only a part of the correct) icon still gets shown instead of the one at those coordinates. If I modify the sprite offset coordinates and then reset them to their correct values, the icons usually show up fine. I also have to make sure my browser cache is purged to get it to work sometimes. (Making sure CKEditor doesn't load files from the browser cache is tricky because some of the requests it makes aren't affected by the "bypass cache" refreshes - Ctrl+F5 or Shift+F5 depending on browser.)

I would recommend going with the Full 4.3 release, but perhaps try a different skin. Wysiwyg does not yet have an option to pick the skin in the UI, but you can override the option by implementing hook_wysiwyg_editor_settings_alter(&$settings, $context) in a small module.

I hope that helps.

I used to switch between CKEditor versions... emptying the Drupal cache and the browser cache too helped me