I was pretty confused about why this even exists (it's weird to read a bunch of paragraphs that are semantically valid but don't seem to convey information), and then I read the [Privacy Notice](
https://www.mozilla.org/en-US/privacy/firefox). Looks like there's a decent amount of surveillance / ad tech built in to Firefox.
From "How is your data used?":
> Firefox also shows its own search suggestions based on information stored on your local device (including recent search terms, open tabs, and previously visited URLs). These suggestions may include sponsored suggestions from Mozilla’s partners
> Mozilla's partners receive de-identified information about interactions with the suggestions they've served.
> Depending on your location, Mozilla derives the high level category (e.g., travel, shopping) of your search from keywords in that query, in order to understand the types and number of searches being made. We utilize privacy preserving technologies such that Mozilla only learns that someone, somewhere, performed a search relating to a particular category, without knowing who.
> Mozilla may also receive location-related keywords from your search (such as when you search for “Boston”) and share this with our partners to provide recommended and sponsored content. Where this occurs, Mozilla cannot associate the keyword search with an individual user once the search suggestion has been served and partners are never able to associate search suggestions with an individual user.
> You may be able to opt into an enhanced search experience, which will result in Mozilla processing additional personal data, including your technical data, location and search data. Some of that information may be shared with our partners on a de-identified and/or aggregated basis.
> We use technical data, language preference, and location to serve content and advertising on the Firefox New Tab page in the correct format (i.e. for mobile vs desktop), language, and relevant location. Mozilla collects technical and interaction data, such as the position, size, views and clicks on New Tab content or ads, to understand how people are interacting with our content and to personalize future content, including sponsored content. This data may be shared with our advertising partners on a de-identified or aggregated basis.
> In some instances, when ads are enabled on New Tab, additional browsing data may also be processed locally on your device to measure the effectiveness of those ads; such data will only be shared with Mozilla and/or our advertising partners via our privacy-preserving technologies on an aggregated and/or de-identified basis.
> When you allow us to do so, Firefox sends Mozilla data about the website domain or specific advertising campaign (if any) that referred you to our download page to help us understand and improve our marketing efforts. Firefox also shares information with our marketing partners to measure and improve these campaigns; what information is specifically shared varies (depending on how you discovered Firefox and your operating system) but generally includes how you were referred to our download page and whether you actively use Firefox. Where Firefox is pre-installed on your device, technical and interaction data (your device type and whether Firefox is used) will be sent to our marketing partners, and shared with Mozilla.