Search form history does not save in latest version of Gmail but does in older version
In the latest version of Gmail, no search form history will save, but it does in the old version of Gmail. I have checked all clear history settings and they are all correct, as it does not delete any other form history including the old version of Gmail. This only occurs in the new version, which is why I've continued to use the older version. I have also checked for plugin conflicts and there are none. I'm on WinXP-SP3 using the latest 3.6.6 version of Firefox.
Gmail may use autocomplete="off" for that form to prevent saving form data.
Here is a bookmarklet to test that: