Visual Editor busted on 2.8.4

When I upgraded to 2.8.2, I lost the visual editor (it’s either blank or it shows HTML). After laboriously disabling/enabling plugins, no go. I finally found the line to add to wp-config.php:

define( ‘CONCATENATE_SCRIPTS’, false );

That seemed to work. Now that I’m on 2.8.4, I’ve lost the visual editor again — but only on one machine. Unfortunately, it’s the one where the person needs the visual editor to work, since they don’t know HTML.

I’ve done the disabling plugins thing again — no change. The concatenate_scripts setting is still in wp-config.php. I’ve cleaned the cache and authenticated sessions, and removed the WP cookies multiple times. The person is an admin user. The Use Visual Editor box is checked (and unchecked and checked again).

This happens on Firefox, and also on Internet Explorer 7 (shudder). The first time I brought a page up in IE7, it showed the visual mode. I walked away feeling good, but my wife told me it failed as soon as she did something with it, and now it won’t show the visual mode again.

One odd thing: in looking at the WordPress cookies on the problematic machine, it shows some cookies that aren’t on the fully-working machine. On my machine, it shows cookies for ‘lastpost’, wp-settings-1, wordpress_logged_in (and some other wordpress_$^@#& gobbledygook cookies), wp-settings-time-1, and __utmz and __utma.

On the problematic machine, there is an extra cookie that shows up after wiping out all WP cookies and logging in again: wordpress_test_cookie.

There is one heavily edited page in particular that doesn’t work, whereas other pages (randomly checked) seem to be fine most of the time.

The Visual editor shows 1 of 2 things:

1. It sometimes shows HTML.
2. It sometimes appears to be blank, although little red underlines show up (from a spell check). I discovered that dragging across the visual editor pane with the mouse actually highlights the HTML — it’s just invisible, but it’s still there. But it’s still only showing HTML, not the visual view.

Any ideas on how to move past this? Is it time to move back to 2.7? I’ve had problems like this on 3 installations since 2.8, and clients are starting to complain.

Thanks for any help!