What is this?

This is an add-on for Mozilla Firefox.

It allows users to change User-Agent string in HTTP header per each domains like RefControl.

Since UAControl was made based on RefControl, its UI and operations are similar to those of RefControl.

Note: this add-on doesn't change strings taken by JavaScirpt (e.g. navigator.userAgent). Instead, User Agent Switcher can handle such strings.


UAControl Screenshot


Firefox 3.6 - 7.* (note: by AMO, it'll be automatically made compatible with newer version of Firefox)

Version History


UAControl :: Add-ons for Firefox



There're some sites recommend to use UAControl to disable Google Instant Preview, but it's possible to cause some bad effect on other Google services. For this purpose, it's recommended to use userscript with Greasemonkey., xxsuke at

Last Modified: 20 Aug. 2011