What do these things have in common? They use JavaScript libraries to work, and if those get messed up, they will stop to function. This happened to me after switching hosts. Since I didn’t have the time to debug this, and search for a proper solution, I simply used this plugin. So, what does it do? Here comes the answer:

Allows your site to use common javascript libraries from Google’s AJAX Libraries CDN, rather than from WordPress’s own copies.

This will prove to be a fast solution for your problems. The plugin is useful even if you don’t have these problems, since it:

  • increases the chance that a user already has these files cached
  • takes load off your server
  • uses compressed versions of the libraries (where available)
  • Google’s servers are set up to negotiate HTTP compression with the requesting browser