How to fix: Clicking 'Quick Edit' link in Admin (edit.php) makes posts disappear?

Question

When I'm logged in and go to the Posts management page (edit.php), if I click the 'Quick Edit' button, the clicked post disappears from the listing!

This occurs in FF7 and Safari 5.1, running WP 3.2.1.

Refreshing the page displays the post in the list again, but I can't find a way to use the Quick Edit functionality.

Edit: In Post management, after clicking quick-edit, Firebug displays: a("input[name=\"ping_status\"]", d).prop is not a function in /wp-admin/js/inline-edit-post.js?ver=20110609

I've tried:

• Clearing the cache in FF, restarting FF, hard refreshing several times (inspired by a post by Andrew Ozz re fixing post edit functionality
• Reinstalling WP from the Dashboard > Upgrade menu (repeat the cache clearing / refreshing)
• Deactivated the most relevant / recent plugins (meaning those that edit the admin area, non essential plugins). I still have a bunch active, but they are crucial - eg Custom Post Type plugins without which the site would break.

Unfortunately, I can't say when this started happening, only that it only happens on this site.

Possibly related issues:

• Clicking the 'Publish immediately' button in the Edit Post page does nothing
• Edit Post: Add a tag / Display most used tags fails
• Yoast SEO: not displayed in tabs, doesn't load the SEO title preview, etc (have switched off the plugin: doesn't resolve the other issues)
• Clicking the 'Edit image' popup button loads the semi-opaque overlay, but no thickbox
• I can no longer upload a new image, though I managed that only half an hour ago :( Upload button does nothing
• Firebug reports: g.prop is not a function, in file wp-admin/js/post.js?ver=20110524

It seems that the jquery / ajaxy business in admin is failing (seeing lots of .prop is not a function). I previously had an issue with adding links in post content, which is why I mentioned the earlier post. Clearing the cache / refreshing worked for this issue.

I'm stumped! Any suggests as to how to proceed would be appreciated,

Regards, Tim

Update: these links are loaded requested twice, but the top ones never resolve ??

Answer 1

Well.. that had me stumped for a while!

I had replaced WP's jquery v1.6.1 with a Google-CDN jquery v1.4.2 in my functions.php.

    wp_deregister_script('jquery');
    wp_enqueue_script('jquery', ("http://ajax.googleapis.com/ajax/libs/jquery/1.6.1/jquery.min.js"), false, '');

Learnt a few things along the way.. thanks, Tim