Yesterday I encountered this problem again, where the wrong search term was passed in the Referring URL, when I clicked a result in Google's search results. I narrowed down that the problem only happened when NoScript was enabled.
More info can be found on this thread that I posted to the NoScript forum.
Other things that I've discovered in the last 24 hours:
When you open the main Google page, the focus won't automatically be set to the search box.
This page has info on using either "https://www.google.com" or "https://encrypted.google.com" for encrypting your searches. It also mentions some of the differences between them.
Using https google.com prevents referring URLs being sent, except for ad links.
Using encrypted google.com prevents referring URLs being sent, including ad links.
You can configure NoScript to force connections to google.com to use HTTPS:
Options - Advanced - HTTPS - Behavior - add *.google.com in the box for "Force the following sites to use secure (HTTPS) connections".
For certain pages to work, the following also need to be configured in the "Never force" box:
With NoScript forcing HTTPS for *.google.com, it appears that no referring URL is sent, even when you click on ad links in the Google search results.
There's no simple/obvious way to update the Firefox Search Manager settings to customize the URL/parameters that get used for each search engine. But with the above "Force HTTPS" NoScript configuration for google.com, any Google searches initiated via Firefox's search bar or the "Search Google for..." context menu item will get sent to the encrypted https://www.google.com site rather than the default non-encrypted http://www.google.com site.
Changing the search engine which is selected in the Firefox Search bar also controls the search engine that is included in the context menu item "Search ... for ...". (It always struck me as preferential treatment that only a Google search entry was included in the Context menu; I didn't realize that it was controlled by the Search bar selection).
In Opera, it is easy to update the URL/parameters used for each search engine. Simply click the Search drop-down, select "Manage Search Engines", and click the "Add..." or "Edit..." button.
This page lets you manually add a search provider for IE7. I didn't test it. It might not work in IE9. There isn't any other obvious way of manually entering your own search provider in IE9.
In Firefox, you can configure whether or not referring URLs are passed (for all sites) via the network.http.sendRefererHeader setting on the about:config page.
In Opera, you can configure whether or not referring URLs are passed (for all sites) via:
Tools - Preferences - Network - Send Referrer information
Tools - Quick Preferences - Send Referrer information
Info on configuring ABE in NoScript. (need to whitelist the domain first)
Crossposted from Dreamwidth. Comments there:
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