Finaly I got it right this time. I bet that most of you faced the same problem as I am after upgrading to WordPress 2.8. WordPress 2.8’s “Visual Editor” is missing.  Earlier I thought maybe it caused by the incompatible internet browser. But I was wrong. Then I “google” (it is really a verb?) it and found that I am not the only one who facing it.

Solution No.1

Add the following code to the wp-config.php file.

define( ‘CONCATENATE_SCRIPTS’, false );

The result is good, fixed the visual editor but it slow down the wordpress admin.

Solution No.2

This solution require your to replace the files contains in the tinymce folder on your server.

1. Open your ftp and log in to server (or access using your CPanel’s File Manager).
2. Go to tinymce folder. (../yoursite.com/wp-includes/js/tinymce/)
3. Delete all files (not folders) in the tinymce folder.
4. Go to http://wordpress.org/download/ and download the latest wordpress file.
5. Extract the compressed file and find the tinymce folder in it (..\wordpress\wp-includes\js\tinymce\).
6. Upload all the files (not folders) into the your tinymce folder on your server. (../yoursite.com/wp-includes/js/tinymce/)
7. Clear your browser cache.
8. Done!

The result was excellence! The Visual Editor fixed and does not slow down the wordpress admin.

Conclusion

Use the second solution, although the solution is a bit tedious but it does not compromise the wordpress admin speed.

Hope it helps you! It sure work for me!

read more: [sticky] 2.8 Problems and Solutions (FAQ) | [resolved] 2.8 upgrade killed visual editor | Can’t edit pages using ‘Visual’ Option in 2.8?