Here's how you can quickly change the default search engine in Firefox in Linux Mint 17 to DuckDuckGo. DuckDuckGo lets you search anonymously and does not track you.
1. Open the Firefox browser in Linux Mint 17.
2. Click the search engine drop down box in the upper right corner.
3. Select DuckDuckGo from the list.
4. If you want to add more search engines, just click the "Manage Search Engines" option in the drop down menu.
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