Just about every web browser lets you specify your default search engine, and some even let you toggle between multiple search engines on the fly. In the upcoming Firefox 71 update, you’ll now be able to set the browser to default to separate search engines whether you’re using its normal or private browsing modes.
This might seem like an odd feature at first glance, but there is a solid use case for it. For example, let’s say you use good ol’ Google Search as your main search tool, since you like having an easily accessible search history, but prefer to use DuckDuckGo when you don’t want your activity tracked. Instead of having to manually swap between the two in Firefox’s settings, you can now set Google as your primary search engine and DuckDuckGo as your search engine for private browsing. Firefox will automatically swap between them when you change your browsing mode.
The engine-swap feature will be available to all users once the stable version of Firefox 71 begins public rollout. In the meantime, you can try out the custom search engine option by downloading the latest Firefox Canary build. Regardless of which version you use, you can set your search engines in Firefox by:
Clicking the three-stacked dots icon, then go to Options > Search.
Scroll down and uncheck “use this search engine in Private Windows” under the Default Search Engine header.
You’ll then be able to select a new search client for Private Mode from the drop-down menu.
Once you’ve specified your preferred search engines, close the settings tab. The changes will take effect immediately.