Hi Thank you for your question. As far as i am aware, Mozilla does not plan to build a search engine and is currently working on making Firefox (on all platforms) even better. There are many search engines to choose from, each with its own strengths, so it is difficult to recommend just one. The main thing I would recommend is to use the one that you want to use. Look at the privacy policies, the design of the page and if there are any special features that you might like or find useful. You may wish to have several set up in Firefox to use for different purposes and tasks. This [https://support.mozilla.org/en-US/kb/add-or-remove-search-engine-firefox article] will help you to change them. I hope that this helps, but feel free to come back here if you need any further assistance.