To harden Mozilla Firefox you should enhance the privacy settings by setting enhanced tracking protection to "Strict", and enabling HTTPS only mode as well as disabling telemetry and choosing a privacy respecting search engine.
Also be sure to update the Firefox browser regularly to ensure it's secure and you can also clear cookies when exiting the Firefox browser and also use Arkenfox user. js configuration file which provides you with a comprehensive suite of privacy enhancing settings.
Firefox makes money through donations as well as royalty payments from search engines like google for making them the default search provider in the Firefox browser.
Other ways for Firefox to make money include paid subscriptions for services like pocket and Mozilla VPN and even from Grants.
Firefox is not owned by a billionaire nor is it owned by Amazon as Firefox is owned by the Mozilla Foundation which is a non profit organization and it's wholly owned subsidiary, the Mozilla Corporation, who aims to prioritize it's users privacy and a secure internet over profits.
Firefox is owned by the Mozilla Foundation and it's subsidiary, the Mozilla Corporation, which is a non profit organization and a for profit entity, and respectively are dedicated to promoting of openness, innovation and also the public interest on the internet.
The Mozilla Foundation is a non profit organization which serves as the parent organization for the Mozilla Corporation.
The Mozilla Corporation is a wholly owned subsidiary of the Mozilla Foundation, which handles the development, the distribution and the promotion of Firefox and other internet related applications.
And both the the Mozilla Corporation and the Mozilla Foundation are guided by the Mozilla Manifesto, which also outlines principles for a healthier and more open internet and prioritizes user's rights and their privacy.
Firefox has never been about maximizing profits and Firefox is not backed by or owned by billionaires and their lone shareholder is a non profit who has a mission to build an open and secure internet ecosystem which places privacy, security and the rights of individuals over bottom lines.