One of the many improvements in WordPress 2.7 is the updated configuration of the visual editor, TinyMCE. It was optimized to support caching better and to load faster.
In my (non-scientific) tests the loading time of the Add New Post screen went from about 5 – 8 sec. to about 1 – 2 sec. depending on the Internet connection and the computer speed.
The removal of the compression whitin WordPress also improves compatibility with some unusual server configurations and fixes some hard to catch errors, for example when there are php errors or output starts in the current theme’s functions.php file.
There are a few steps that would help with the troubleshooting if the editor doesn’t start or work properly:
- Make sure the “Disable the visual editor when writing” checkbox in your profile is not selected.
- Whitelist or set your blog as “trusted” in your firewall and antivirus program.
- Disable Gears, clear your browser’s cache, quit it, start it again, go back to the write page and force-reload it several times, while holding down Shift (Firefox) or Ctrl (IE). In Safari select Clear Cache (from the Safari menu on Mac).
- Try another browser and/or another computer.
- Disable all plugins, clear the cache, restart the browser and try again.
- Delete both
wp-includesdirectories and upload fresh copies from the WordPress installation package.