- In Internet Explorer, click Tools → Internet Options..., click the Content tab, click AutoComplete and there are options there. Uncheck the box for "forms" (and "Web addresses" and "User names and passwords on forms" if you want) and click "Clear Forms".
- In Firefox, to disable the feature go to Tools → Options..., in the Privacy section, click the Saved Forms tab and uncheck "Save information I enter in forms and the Search Bar" and click OK and then click Tools → Clear Private Data... and make sure Saved Form Information has a tick and then click Clear Private Data Now. It's up to you to determine what other data you want to clear.
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