The largest web properties pushing Firefox to users, or perhaps social media campaigns. It's an outreach effort, the technical details are already solved. Make the Google/Chrome brand toxic.
This is how Internet Explorer (via Windows), Chrome (via Google Search and YouTube) and Safari (via iOS) gained significant market share. Through another platform or service that they owned, that they could use to promote their browser.
But large Web properties do not gain anything by promoting Firefox. Many are ad-supported, so getting rid of uBlock Origin is a good thing for them. Only having to test on Google Chrome (and maybe Safari) is cheaper for them. There has to be something in it for them to promote Firefox or an alternative browser.
https://blog.mozilla.org/en/privacy-security/how-to-switch-f...